Starting last Wednesday we started making cuts out of latex to apply to our skin.  I chose this picture to model my cut after....
I took some liberties with it... I designed the shape of my cut after the one above, but I made it larger and wider.  On Friday we used the spirit gum to adhere our pieces to our arms.  Here is a picture of mine right after I put it on:
Obviously there was some excess around the edges that I had to trim.  We then applied our base foundation to try to match the piece to our skin tone.  This is where I had some trouble.  I mixed the foundation I use for my face and found it to be too dark, so as Sue suggested, I used my highlight and went around the edges of my piece.  It did help, but it still needed some work. 
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| That's the closest I could get it in class. | 
We then added the makeup to the inside of the wound to make it look like a scar.  I added some purples and reds from the bruise & abrasion pot....
Then we added red and blood to make it look like a fresh cut...
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| BLOOD! |  |  |  |  |  | 
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I took note that I was going to have to work hard to match the skin tone once I put the wound on my face. On Monday when we put them on our faces, I had the same problem. I spent most of the time trying to match the color of the latex to my own skin.  I trimmed my appliance down a lot, hoping it would help with hiding the edges, but the inside edge was still a very visible.  Here's some step-by-step pictures:
Then we added color.  Along with the red inside of my cut, I added some bruises around my eye and along my temple....
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| That edge really bothers me. Grr. |  |  | 
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| Then I added some blooood. |  |  |  |  |  | 
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| It was very drippy. | 
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| And some morrre blood. | 
Next time I think I want to my cut deeper, but the outer edges thinner as to try to reduce visible edges.  That was my biggest problem I think.  If the wound had more depth, I think it would have been more realistic... or maybe just more gorey.  I'd love for you to comment with some advice!