Items you will need:
-Gelatin-skin (a great tutorial here --> http://www.zombiemaker.com/makeup/gelatine_skin_basics )
-Face and Nose Wax (or any sort of make-up wax will work)
-Toilet paper (2-ply)
-Eyeshadow in bruise colors (yellow, blue, green)
-Cream make-up (red, yellow, blue)
-Face powder (or Neutral Set)
-Liquid Latex (optional)
And some great music to listen to never hurts :3
Step 1: Getting Started
Step 2: Wax time
If it starts to stick to your fingers, wipe them off on a dry paper towel. Getting your fingers wet while they're covered in wax will only end in tears.
Step 3: Toilet paper time
After you have as much as you want (seriously, go crazy), take the red cream make-up and a brush and start splotching the red onto the toilet paper.
Step 4: Still coloring...
Then, mix together a bit of blue and yellow to make a nice green, and add that as well.