Well I TRIED making an open wound today, even though I have like nothin to work with, no wax, no spirit glue, wrong tools and not even a good RED color!!! I had like orange-red and purple-red! So I'm going to need to get a RED color!! ;)
I make a home made prostatic gel though it worked great!
You only need gelatin, glycerin (or glycerol) and water!
You mix equal parts of the 3 ingrediens and mix, put in the microwave for 10-20 sec on high temperature then stir around and put it back for another 10-20 min then take it out and wait 5-10 min for it to cool down and harden. The. You stroke it on you skin and wait 5-10 min. Then you cab do whatever you want! I made a hole and scratched the prostaticgel outwards so it looked like flesh!
Hope this helped you and I promis I will come back with better results! Remeber it was my first time doing this;)