I have lost a little of my material room knowledge but I need to try to combine three parts  of a texture into one diffuse. I have the base skin texture and I want to add a scar layer in a certain color (call it red) and then I want to add a hair layer in a certain color (call it black). If I could get a touch of assistance with the blender nodes I would appreciate it. I have an older file someplace that I do something similar (beard and superhero outfit on top of diffuse) but I can't find it on my other machine.

Thanks, in advance.