Step 1:
Color your flats, but instead of filling them with mid-tones
fill them with the color you want the darkest shadows to be.
I find it can also help to have a dark color in the background
as well. |
Step 2:
Decide where your light source is. This technique works well on
more realistic anatomy and/or unusual light sources, so I'm
going to pretend that for some reason the subjects hand is
glowing and that's where the light for the picture is coming
from.
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Step 3:
Now choose an area to start with and pick a color between your
shadow color and what you want to be the lightest color. My
shadow color is a dull purplish red and my lightest color is
gonna be a bright yellow, so my initial highlight color is a
peach. Imagine where the light from your light source would hit
your subject and put the color there.
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Step 4:
Continue using colors closer to your highlight color until the
section is fully highlighted
 |
Step 5:
Do the same thing to the rest of the sections.
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Step 6:
This coloring method doesn't just work for unusual light
sources. It can be used for a generic light source as well.
Flats
Skin highlight color 1
Skin highlight color 2
Skin highlight color 3
Whole image highlighted |