On occasion I receive messages asking how to mix soap dough colors.
Ideally it is preferable to make the soap dough with the color mixed into the oils before lye-water is added. I use soap stable micas; some from TKB Trading, Nurture Soap Supply and a few other places.
Read about more about soap dough and how to mix colors here: "An Enchanted Book of Peculiar Ideas and Soap Potions."
First try making the basic colors, or primary colors - red, blue and yellow. With these prime colors the secondary and tertiary colors can be made. Having white soap dough will give tints of any of these colors.
Here is a video sharing when soap dough has not been made properly and what it looks like when it has been made properly.
If you would like to use my recipe here is pre-made Sorcery Soap dough with all the magic that can be packaged into each bar.