So, My most ambitious costume to date was to create a Wearable smoke breathing dragon. This costume could easily be converted into a prop for freaking your neighborhood out!

I learned a few things along the way, and have tips for anyone who may wish to create something similar in the future. This instructable has been modified to include all steps needed to build the entire dragon.

One Optional Part is the Smoke machine, which runs off a 12 v power supply. See "Smoke Machine"

Parts needed.
1. Aluminum frame backpack
2. PVC Plumbing Pipe
3. several Nuts and bolts
4. 6-8 large cans of Spray Foam insulation
5. Spray Paint in a color of your choosing. I used 3-4 different colors of Green for the main body and a metallic Copper for the accent pieces
6. 150-200 hot glue sticks.

Tools needed
1. Hot Glue Gun
2. Sharp Steak knife
3. Rotary tool for details.
4. Blow Torch
5. Safety goggles
6. dust mask

Optional parts
1. Replacement harness for backpack (more straps = more stable)
2. portable Smoke machine (Instructable to follow)

Download

Step 1: Planning - Draw It Out

Before you dig into the actual details of what you are building, you must first figure out what it is that you are going to build and how big you are going to go.

Some considerations
1. Ceiling heights
2. Doorways

After completing the costume, I am glad I didn't end up going any taller then i did, as i had some minor issues getting into doors, but most bars/clubs were high enough ceilings that it wasn't an issue.

Sketch out what it is you wish to build, and plan for the size.

Step 2: Head - Trial and Error, and Things to Avoid :-)

Okay, So I admit that I got a little overzealous and didn't appropriately plan things, which caused me to spend more time and money with the spray foam then I would have liked.

In any case to create my head, i did the following.

1. Take an old windshield washer fluid bottle and cut, roughly in half diagonally.
2. Place the bottle on a flat surface (preferably one you care little about as the next step will make it much less valuable)
3. Cover the bottle in a good helping of spray foam. try to spray it evenly so there are not deep pits and holes as you may run into issues when you end up sculpting the face away.
4. Let it sit overnight to completely cure
5. Repeat but with a smaller amount for the lower jaw. You will want it to be roughly the same length, but not quite as deep.

Tips or alternative methods things
1. A friend of mine used a paper mache type solution similar to https://www.instructables.com/id/Make-paper-mache-pulp to do a dinosaur skull which may provide an alternative to spray foam core, That way you can do mostly a Shell, with a textured skin over-top.

2. Make a basic shape out of chicken wire, covered with Masking tape or Newspaper, this will give you a base, and will also allow you a shell, and save in the spray foam. Once the spray foam is set, the core can be removed.

Once you have your base foam shape, its a matter of making the head look the way you want.

I did some base drawing with a sharpie to figure out where the nose, eyes, beak etc were going to be and began cutting with a simple steak knife.

Any detail work can be done this way or you can use a Dremel (I used the Dremel to get the exact shape I needed around the eyebrow ridge, and the nose. The knife just couldn't get into where I needed it to)

I used a steak knife for 85% of the sculpting.

Once the head is done you can do a couple things to strengthen it. Cover it in a fiberglass Bondo or Auto-body filler, Paper Mache pulp with carpenter's glue.

I decided against the strengthening due to time constraints.

Step 3: Spine

Although the majority of the head will be lightweight and foam, it is important to build a support column for the head.

I cut 2 pieces of PVC plumbing tubing and attach to the backpack. If you have a cross bar at the top of your backpack, it may be wise to attach to the back of the backpack, to keep the added structural integrity of the aluminum cross members.

My backpack did not have the cross member, and i was lucky enough to have the PVC slide into the aluminum tubes.

2 nuts+ bolts in either side to ensure that it didn't flop around.

Bending over the pipe with hot air gun may be doable, but i found that it wasn't required as the weight of the head, combined with some leaning will give you sufficient shape for a decent neck curve

A curve in the front is recommended to both provide you some space to know where your vision line will be (roughly) and give you a place to attach a 3rd bar for the front which is helpful in skinning the dragon.

NOTE: I had also added a vertical brace to help it to hold its shape when covered in the foam skin found in the next step, Unfortunately I don't have pictures of those steps, but I've added a picture with the braces drawn in so you can get the idea. These braces were all removed after the foam skin dried.

Step 4: Neck Covering.

This here i found myself wasting more foam then needed as well.

After i had the spine + Skeleton from step 2, I had a rough shape available from the neck

What i did:
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1. I covered the shell, front to back, with wide masking tape, allowing me a rough skin to give a covered shape
2. Covered the masking tape (in 3 sections) with spray foam. You will have to let it set before moving to the next section otherwise the foam will slide off or drip making a terrible mess
3. Slice a bit into the set side, when moving onto the next section to allow a permanent meshing between the sections. This will both add stability, and strength.

Once all three areas are cured, the tape and added spine portions can be removed to lighten the head, and to leave additional room.

Once all the tape is removed, you can also sculpt it out additional space inside with either a knife or a Dremel. More space means more room for heat to travel, escape through the mouth, and it will also take a lot longer to get hot inside.

Things to try next time.
1. Chicken wire + Cloth skin. This will likely add some weight, but save in cost, due to the expense of the spray foam and the amount of material that may be cut away.

Step 5: Texture.

Gotta love when an accident ends up working for you and saving time. The texture of my dragon was going to be a problem. I wanted something scaly or warty but was not sure how i was going to get it done.... then... an accident

Here's how the accident works.

1. Cut your new covered neck somewhat smooth with either your Dremel or knife leaving plenty of space but large 'flat' pieces
2. Cover the now somewhat smooth neck with a covering of more spray foam.
3. Use a putty knife, and attempt to smooth the new spray foam over the neck, you'll see where it's sticky and a bit of a different color. spreading evenly isn't required, but the more you spread it the better overall effect
4. Let it dry.
5. Presto. warty/lizardish Hide.

This method will be used again for the Legs, and the (Shoulders/upper arms)

Step 6: Teeth

Teeth are created using Hot glue-sticks melted with a blowtorch. Surprisingly simple yet effective. NOTE: Use of a blowtorch can be dangerous. Be sure to remove any flammable objects from your workspace and work in a well ventilated area due to the potential fumes from the burnt foam.

1. For the big front teeth, take 3 hot glue sticks, and glue them together in a triangle.
For smaller teeth, 1 large glue-stick is usually enough, however some used a large glue-stick with 2 smaller glue-sticks glued on (in the same fashion as the big teeth) but cut down by about 1/3rd.

2. Melt a hole in the upper jaw so the glue-sticks sink in about 1-1.5 inches (so they are not easily snapped out) and fill the remainder of the hole with glue from your glue stick so that its stable.

3. With the head upside down (teeth sticking upwards), melt the top of the glue-sticks with your blowtorch. You will see it begin to drip down a bit, which is fine. Once the tip starts dripping a little bit, gently melt the sides a little so that the tooth takes a general roundish shape and the 3 sticks sort of melt together a bit to make one large one.

4. Let the tooth cool a little, so the glue is still a bit mold able, and with wet fingers, shape the tooth into a point.

5. Repeat for other teeth.

This is also done for the lower jaw.

These steps will be used again when creating the claws for the hands and toes.

Additional options.

You could add LED's to the base (where the tooth and jaw meet) inserted into the tooth if you wished it to glow at this point, I'd recommend having them wired first so you don't have to do any fussing about with wires, and solder after the teeth are firmly held in place.

Step 7: Accents and Details

So the head is all built now, finally you can do things like add accents, Horns spikes etc

I decided to change the types of horns that the dragon had, and to give myself a little more height clearance.

To do this, I again used 2 pieces of PVC Plumbing pipe that I had,

1. Cut the PVC piping to the approximate length of the horns you are adding.
2. Drill into the skull of the costume approximately 3-4 inches ensuring that the bit is about the same size as the piping. Using a slightly smaller bit OK, because the foam will hold it tight

3. Use a hot air gun or blow torch to bend the PVC Pipes to the curves you want.

4. Cover 1/2 of the individual horns with the expanding foam to give it a look you wish. You could also use the Paper ache, or the Light Weight air dry modeling clay to give it a more sharp look. Be sure to allow the 3-4 inches on one end to be clear so that you will be able to more easily insert the piping into the head. : Note, I covered mine AFTER i'd hot glued them into the head, to allow for a more clean join where the head met the horns.

5. Let the Foam/glue/Clay dry, and then do the other side

6. liberally cover the ends of the PVC pipes in hot glue up to 3-4 inches and insert into the holes you've bored into the skull.

Spikes
The spikes were literally pieces of left over foam that were cut off from the inside of the dragon from previous steps
1. Cut a flat strip along the back of the dragon's head/neck
2. Cut Your larger foam cast offs into spike Shapes
3. Hot glue the spikes to the flat space left along the neck/back
4. Spray paint the appropriate color

Step 8: Feet

Hands and feet were easily made again using some foam that I had left over.

I used a different kind of foam here, from some packaging material discarded from work. This foam was a more plastic feel, and was able to withstand the stepping/kicking etc more readily then the cut spray foam.

I was also lucky enough to have some large, thick pieces that made cutting the feet out of single pieces

Part A : Feet
1. Starting from the large block of Plastic packing foam. Grab one of your shoes (running shoes in my case) and draw a rough cut out on the size of the bottom of your shoe

2. Draw in an outline of your dragon's toes, note, no claws are needed, they will be added later with the same method used to make the teeth, but with 3 Large Hot Glue Sticks instead. (black outline)

3. Since your shoe is going to fit up inside, and be attached directly to the foam, you'll need a place to put your foot through, so this gives you a place to start. Cut out all the way through the foam, where your foot will go (blue oval)

4. Carefully cut out the inside of where your shoe will go, taking your time, as cutting away too much may make it difficult to get a proper seal when you move to the next step

5. Hot glue the Shoe to the cavity inside the foam block. Be liberal with the hot glue, or your shoe may come out through wear much sooner then anticipated.

6. Carve your toes, rounding them out, and add detail if you wish (joints)

7. Cut/Melt some holes into the ends of the toes, where the claws will be inserted.

8. Using the same method used to make the teeth, hot glue 3 sticks of Hot Glue together in a pyramid shape and then hot glue the ends, inserting them into the holes

9. Using your blow torch, carefully melt the ends of the glue sticks first, and then warm up the remainder between the points and the toes.

10. Let sit for a few moments to cool slightly and then shape using wet fingers.

11. Tape off the joints where the toes meet the claws (on the claw side), and spray paint your feet the appropriate color (in my case, more of the camouflage green color)

Step 9: Hands

Hands are made in a similar manner to feet, but as they have more joints, and you'd probably like to be able to move them, you will have to have more pieces joined to make the fingers.

Finger
1. Using the same foam used in the previous instruction set, cut 10 longer rectangles, roughly 3-6 inches long, These will be the last bend in your fingers

2. Round the rectangles, sculpting them to more finger shaped pieces

3. At the glove end, carefully melt into the end, 2-3 inches a hole that your glove will fit into snugly

4. add hot glue to the inside of the hole, and with one hand wearing the glove, insert the foam finger, onto the finger of your glove. Note : Depending on the glove you use, the hot glue will still be quite warm. You may wish to allow it to cool slightly before pushing the finger onto your glove

5. Repeat for the remaining fingers.

6. For the back of the hand, cut a reasonable sized piece of the same foam to the size of the back of your hand, and hot glue in place

7. Cut smaller bits for each of your digits, between knuckles and hot glue them in. The foam here bends pretty well, so it's possible if you have long enough pieces of foam to just use 1 long piece for the entire amount, melting a U shaped channel into the foam and gluing that directly onto the entirety of one finger of the glove.   This could save a lot of time and save some fussing to make the joints stay glued together.

8. Again using the same method used in the previous step, make claws with 3 glue sticks + blowtorch.

Since my dragon wore armor, and Time was running out, to make a fore-arm I used a piece of black carpet underpad.

9. Measure and Cut a piece of black carpet underpad (obtained at Home depot) into a rough cylinder. One end will be slightly more then your glove opening, the other, as large as you wish the arm to be

10. To ensure a good join, I glued a strip along one edge where the cylinder would join to it's self, and allowed to cool.

11. Once the "joint" is cool, fold the edges together and line up. Hot Glue the strip and place the edges together, lining them up.   Placing something heavy on the "gauntlet" at this point can free your hands up while the glue is cooling and the joints are solidifying

12. Repeat for the other side

13. Once the cylinders are cooled, hot glue your gloves to the smaller end inside the glove. Besure to do this all the way around the glove, as you may have to be able to force your hand inside the glove to wear it properly

14. Where your elbow bends, you may also need to cut an arc in the carpet underpad, which will allow you to bend properly

15. add embellishments, such as arcs, spikes , or in my case, Knuckle protectors to give it a personal flair.   You could also add jewels and what not, but wouldn't recommend this until you are done painting

16. Hit the carpet underpad with your torch slightly, to melt the edge of the underpad foam, giving it a slightly smoother, more metallic look

17. Paint your underpad "gauntlet" the appropriate colors, and add any final decorations you wish ( bloody smears in my case)

Step 10: Legs

For the legs, to give it the appropriate size and shape i wanted, I followed step 8 instructions from @MissMonster 's How to "Build a Realistic Werewolf"

I used an old pair of jeans that i had been using up to this point, for working on the other steps, they'd already been covered somewhat with bits of spray foam, and hot glue, so they were a worthy sacrifice to the Dragon.

1. Pad the top of the leg above the nee, and the bottom of the legs below the knee, to give your legs more massive look.

2. Cover the padding with a cloth material, and glue it down

3. Next, lay down a layer of spray foam over the cloth, and use the putty knife to "smooth" it, allowing you to again get a grainy/bumpy/warty texture the same as you accomplished in step 5 of this tutorial

4. Once the top half of the legs are dry, and the spray foam has cured, flip over the legs and do the same for the back

5. Once it's dry, all you need to do is paint them the appropriate colors

Step 11: Dragon Armour

This is where things get a little tricky. Because you will be wearing the dragon over your head, his body will probably be much more massive then your own.   It may be a bit tricky, but always leave extra room

To do this correctly I first did a Cardboard template of what the armor I wanted to look like, and then I dismantled it, and built it out of the carpet underpad for a more durable, and more metallic look.

First, Start at the shoulders.
1. Figure out how wide you wish your shoulders to be. I lucked out, by having a Large Styrofoam flower pot for covering your bushes in winter available, and just cut this in half.

2. using some nails, or sharpish pieces of wire, pin the pot to the dragon's lower neck, figuring where you want the dragon's shoulders to be

3. Cut 2 large rectangular shapes (rhombus) that will go from the shoulders, to join in the middle of the dragon's front.

SINCE this is where my eyes were going to be, I wanted to add some symbol or something that I could see out of, but needed a way to make it large enough to see out of.

4. Cut a large square (diamond) for the middle where your eyes will see out of, and join the 2 shoulder-middle rectangles in the middle

5. Cut a strip for the middle where your pieces will eventually join, and attach it to the underside of your diamond

6. Cut 10-16 strips of equal width and length of cardboard and overlap them slightly to get a scale/stair effect, tape them so they hold

7. Cut an angle into the strips so they line up and hold.

8. Attach them all together. Bend part way up the front, so that it will curve a little easier when you are ready to join to the back

9. Do something similar for the back armor. I ended up using only 3-4 very large overlapping pieces for both simplicity and time constraints.

10. This gives you a cardboard template to work from, you'd be able to cut the shoulders/front joint into a single J like shape that you can use to cut specific pieces out of the carpet underpad.

Using the "pattern" you created in the cardboard, replicate in the underpad and glue as necessary

I glued the back armor directly to the back of the dragon which gave it both a proper curve, and some strength. Be sure to allow enough room that the back armor will come at least to the half way point where your dragon's shoulder will be.   You will have to cut a hole for your own arm to come through, but this will allow it to be more stable and free to move.

Attaching the Chest plate to the head is accomplished using clips.

I found the clips at Mountain Equipment Co-Op but you should be able to find them at any fabric store as well (see pictures)

6 clips were used for the attaching the chest armor to the dragon head/back.

Preparing the clips

Cut several lengths of nylon webbing for the straps to work through.
For attaching to the Head, you'll need several longer lengths, as you'll be punching through the head, and gluing it solidly in place, to prevent tearing through the spray foam, and to ensure that it will hold the weight of the chest plate

Since the head is not easily fed through a sewing machine, liberal amounts of hot glue were used to attach the ends together and seal one end of the clip for attaching.

All other ends of the clips had the webbing sewn so there was no chance of the clips sliding/falling or otherwise coming undone.

Positioning
Clips are attached in 3 places on the left, and the same 3 places on the right

1. 1 top of the Chest armor, to bottom of the neck
2. Top of the Chest armor to the top of the back armor
3. Bottom of the Chest armor to to the bottom of the back armor

All clips are done INSIDE of the armor to allow the clips to be hidden, and placed in such a way that the wearer can release them if needed.

Attaching
Attaching to the neck is easy. Once they are glued into place, attach the other half of the clip, and mark on the inside of the armor where the webbing is to attach.

Hot glue the ends liberally and attach the other half of the prepared clip's webbing where you've marked it. allow to dry, and move on to the side markers. Do one at a side, to allow you to attach/detach the armor on each side, folding over for ease of marking the other side.

Finishing up the armor
1. Hit the metallic look by hitting the armor with the blow torch. Carefully melt the top layer of the underpad foam, giving it the metallic look from the gauntlet steps.

2. Draw a symbol on your vision triangle. I wanted something reasonably large but dragon like, to allow me to see better. Carefully cut the material out, all the way through.

3. Spray Paint the armor the colors you wish

4. Attach a piece of plastic mesh,or dark see-through material on the inside of the symbol so you can see out, and unless others look really carefully, they won't realize that is where you see out.

Step 12: Try It All On

Start putting on your pieces.

The order that worked best for me were the following

1. Pants
2. Shoes(feet)
3. Backpack/Dragon Head
4. Chest Armour (needed help to get all clips done up for the first 3-4 attempts)
5. Gauntlets

Note any adjustments that may need to be made, such as the raising/lowering of the chest plate, for vision requirements.

and finally...

Practice your roars, and menacing poses.