Guide Comment: Lisa, its an excellent effort. You've put a lot of thought into this drawing and the shading and detail are good. You are tending to look at the hair as separate strands, and I suspect the model hasn't helped - sometimes if the hair is messy you have to make choices about what to leave out, to make life easier for yourself. Try to see the hair as ribbons or sections of hair - the shading changes along the length - then separating out some strands by drawing in the shadow behind them.

Take a look at my tutorial on drawing hair