Painting and finishing porcelain dolls?

I was wondering what most people do to add color to and finish up their porcelain casts? Does it work better to cast in a colored slip, or add color after, and what colorants are commonly used for skin tones? Is the clay left unglazed or is a thin matte glaze added? What is used to add blush and faceup?

(Sorry if these questions are obvious or get asked a lot! I'm really new to anything beyond pretty standard ceramics, but I have a school project on slip casting and thought it would be a good time to learn!)