This is the way I use to draw hair:
1. the scan of the original photo reference.
2. I finish my sketch and fill in the shape of the whole character with a dark color before starting to draw. That colored part on the right is the face, which I finished before drawing the hair.
3. I pick a brush, set the transparency to a very high level (about 95 of 100) and begin to sketch with some bright brown/yellow. I always use a grid when drawing after a photo reference.
4. use the smudge tool (again with high transparency) to work out the shape of the single strands of hair.
5. now I start to work on the details. I permanently switch from the coloring brush to smudge tool and back again to get the highlights. For the coloring brush I pick a bright yellow, almost white. And again with a high transparency. The things in the foreground will be finished at last.
6. Finally I add some last details like the tiny hairs (lower the transparency of the brush to do this), which hardly can be realized in the final submission, but I want to have them there.
If you got more questions or you just can’t understand my English
feel free to ask or send me a note.
View the finished drawing: [link]