Fun fact: Whenever I paint a portrait I always paint the eyebrows last. Weird, I know. But it is quite interesting to see what people look like without them.
Tip: Always start a painting from the eyes. Not the hair. Not the face. From the eyes. Eyes are usually the focal point in portraits as they somehow hold all the emotion. Don’t worry about putting too much detail in the hair or neck area, because you want the focus to be on the face.