I have a simple method to paint ork flesh. I only use 4 paints and it is fairly easy to batch paint using this method, which is a good thing when you use the green tide tactic and have loads of boyz to paint!
Stage 1
The first stage is to apply Waaagh flesh using a basecoat brush.
Stage 2
The next step is to apply the wash biel tan green using a wash brush.
Stage 3
Then using the standard brush apply warboss green to the raised areas of the flesh.
Stage 4
The final stage is to use the detail brush to apply skarsnik green.
Better pictures will follow to demonstrate this better, I will also be adding more detailed guides on how to paint each of the clans I currently collect.