Here are some of the steps that I use to paint
1- Paint the face with yellow ocre and Burnt sienna.
2- Put white over the other colors on the lights.
3- Then the colors fade.
4- Put Burnt sienna again over the shadows and a little cadmium red on the cheeks .
5- Fade them again.
6- And do the details like: Mouth, eyes, ear, nose and hair.
All these steps are at the same time, I mean, when the paint is wet.