HOW TO PAINT A PORTRAIT: STEP 4
Adding Midtones
This is the first introduction of oil colour to the painting. You’ll need to mix up a generous amount of mid-tone skin colour (or your subject’s main colour). This is done using the three primary colours. For light skin, start with yellow and add hints of red then blue. For darker skin start with blue, then add hints of red and finally yellow. Use white to lighten the tone if you wish. Dilute the paint with turpentine so that it’s almost transparent, so that the initial underpainting will show through, and use this to cover the entire skin area. While this tone is still wet, mix some white into the paint, add a bit more turpentine and begin to paint in the lighter areas of skin.