This instructable outlines how to make a 3rd degree burn for your arm or other appendage. I have used this for some costumes and it works for training people to treat burns.

Step 1: Materials Needed

-Elmer's Glue
-Black Aerosol Hair Coloring
-Fake Blood
-Tissue Paper
-Sharpie

Optional:
-Black Skin Makeup

You can find the Hair Coloring at most costume shops.
The fake blood can be substituted with red food coloring/red paint.

Step 2: Put Down the Base

(If you have the black makeup, smear that on your body part as the base)

Smear the glue on your arm (or other body part), make sure the edges are well defined and where
you want them. A thin layer will dry faster.

Take the tissue paper, rip it into an irregular shape roughly the shape of your intended burn and push it firmly on top of the glue. It should not be flat, make sure it bubbles up a bit. Doing two layers of thin tissue helps the bubbling effect. Depending on how much time you have, I suggest you build up a layer of two or three tissues.

Allow it to dry completely, then add another layer.

Step 3: Coloring

Take the black hair spray and paint the burn.
It helps to shield the parts of your arm that are not part of the burn to avoid over spray.
Clean off the overspray with a slightly damp towel or tissue. It will smear, just do your best to get rid of most of it.

Step 4: Final Touches

Add the fake blood, allow it to run and smear it around, especially the edges of the burn. It will make the wound look oozy, as well as cover up the edges and any spots you missed with the spray can.

Step 5: Conclusion

As you wear it, the fake blood will dry giving it a scabbed/crystallized look. Add more blood to keep it looking wet, but it still looks good without it.

When you're ready to take it off, run the body part under warm water and wait for the glue to soften. It will come off much easier than trying to rip it off. My arm was a little red for maybe 3 minutes afterward. But that is because i'm impatient.

I had a doctor comment that it "look as real as what i've seen".

Please leave comments, This is my first instructable, so it is very likely i've left off some vital information or made this very hard to understand.