Greetings here is my tutorial for painting green skin, first shared on the blog's Facebook page.
Stage 1:
Primer - Tamiya Fine Surface Primer Light Grey
Base coat - Goblin Green 72.030 Vallejo game Colour
Stage 2:
1st Shadows - Sick Green 72.029 Vallejo Game Colour
Using a thin downed coat of Sick Green, begin sketching in the areas of shadow. You can add multiple thin layers to increase the intensity of the shadow.