At the CRASHspace InstaMorph build night, I'd planned to make a custom stand for our mascot Sparkles. However, as soon as the pancake of plastic grew large enough, I suddenly changed plans and opted to make a mask instead.

Check out the instructable showing some of the other projects we made. There are also a lot of good tips for this particular material that we discovered through experimentation.

Yes, that's me in the video, experimenting with hot plastic on my face so that you don't have to. As long as it's heated only to the recommended temperature, it's actually not at all uncomfortable. Note my noise of surprise when I first put it on.

After doing this full-face version, I decided to make a half mask and decorate it. You can go full-size if you want, but I'd recommend making a mouth hole to breathe through first.

Step 1: Materials

InstaMorph
Large pot or bowl
A source of heated water - you can do this on a hot plate (like I did), on a stove, or by heating the water another way and adding it to the large pot
Thermometer (optional, but handy)
Tongs or pliers
Appropriate work surface (I used aluminum foil)
Cutting tool (like a craft knife)
Cord, elastic, or other string
Hot glue gun and glue (dual temp is helpful)
Items to decorate your mask with (beads, rhinestones, permanent markers, etc)

Step 2: Setup and Tips

You'll want a large pot of hot water. I put mine on a hot plate, but you could also use a stove. A thermometer is helpful, so you can make sure the temperature is right. InstaMorph recommends 160°F. If it's boiling, it's too hot, and will hurt to work with.

It's important to have the right surface to work on. When I made my full mask, I worked with the plastic directly on our plastic tables at Crashspace. When I did the half mask later, I initially put it on a cutting mat, but it became apparent very quickly that it would stick to this surface. Aluminum foil is a safe and readily-available option.

Step 3: Making the Mask Base

These photos are helpful, but check out my video of the process to really get a good idea of working with InstaMorph to make your mask base.

The basic idea is to heat up the plastic, press it flat, put it back in the hot water, and repeat. Reheating it periodically will give you a smooth pancake of plastic that you can keep working til you have it as thin as you want. There's no "correct" depth either, but I usually take it to 1/8-1/4" thick.

Be careful not to let the pancake fold up and touch. It messes up your nice smooth surface, as the stuff sticks to itself immediately and doesn't come off easily. Fortunately, if this happens, you can just chuck it back in the hot water and re-form it.

When you are ready to put it on your face, make sure it's not too hot (it shouldn't be completely transparent, that's too hot), and go for it. If you're doing a full face mask, do yourself a favor and cut a mouth hole. If you forget to do this, you probably won't get your face stuck and suffocate, but it's harder to get a good mold when you have to keep pulling your chin away to take a breath.

Mold it to your face, making sure to poke it into all of the nooks, like around your eyes, nose, and mouth, and around the sides of your face. Keep on pressing it into shape until it's cooled somewhat. You'll be able to tell when it's holding the shape pretty well. Also, note that whatever unintentional face you are making will be a part of it. It you're cringing, you'll be able to see it.

Step 4: Shaping the Mask Base

Once you have the plastic molded to your face, you'll probably want to carve it down. It's much easier to do this as a separate step, rather than trying to get just the right shape while the plastic is still hot. It will be on your face, and your eyes will be closed.

I like to start out by cutting very small holes for the eyes. Once you can see, it's easy to use a Sharpie or other permanent marker to sketch out where you'd like the full eye holes and outside edge of the mask to be. Use a craft knife to shape it.

Be careful with the knife. This is a curiously textured material, it feels a bit spongy to cut, and however careful you've been, it will have some inconsistent texture. Always cut with the knife's blade pointing away from yourself. You can use the hot end of a glue gun to help smooth out the edges if you'd like.

Step 5: Attaching the Band

Using your craft knife, or a drill, make a hole on either side. Pull a cord through and tie a loop behind your head. Easy peasy.

Step 6: Decorating the Mask

I mentioned that a dual-temp hot glue gun is helpful. Part of the reason is that a high-temperature glue gun is likely to get the plastic hot enough to melt again, which does make the adhesion better, but also opens the possibility of warping the shape. Low-temp glue will hold its shape a little better, which makes it easier to place the items.

I started off by surrounding the eyes and moved out from there.

Step 7: Fin

And that's your custom mask! Make as many as you want, they're pretty straightforward, and you can decorate them in different ways.

The first three people to make a mask using this instructable and post a picture will get a neat mask patch for their profile!

Step 8: Alternate: Hot Glue Mask

You know that full face mask I made back at the beginning? I decided to use it as a base for making custom hot glue masks. Just squeeze patterns onto the mold in low temp hot glue (high temp setting will make it harder to remove), let it cool, and peel it off. You can make as many as you like, very quickly.

You can make holes at the sides so as to tie them on with a string, or, since they are so very light, you can use a little bit of spirit gum to tack it straight onto your face.