Here's a tutorial of how I paint faces on my figures. For this tutorial I used GW paints, and a figure with a black undercoat.
Step 1:
Paint the face with Dark Flesh.
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Step 2:
Paint the nose with Dwarf Flesh.
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Step 3:
And then the upper lip with Dwarf Flesh too.
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Step 4:
Mix 75% Skull White and 25% Blood Red to get a bright pink.
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Step 5:
Paint the whole face with Dwarf Flesh except the chin.
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Step 6:
When that's done, paint the chin with Dwarf Flesh.
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Step 7:
Paint the ears Dwarf Flesh.
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Step 8:
Finally, highlight the cheeks, the chin and nose with Elf Flesh.
Now the rest of the fig...