The first step to drawing hair is realizing that you don't need to draw every single hair. When you look at someone's hair you see a mass of texture, but not every single strand.
The BASIC (very basic) shading of the hair is a lot like a ribbon with the highlights and shadows in it's dips and twists.
The strands are then added in to give the ILLUSION of precision.
Here is an outline of hair. Note that it follows the curve of the head since your hair naturally just hangs off of your head.
Throw in some basic shading. Note that the hair partially hidden by the neck, head, or other hair will be darker. The rest of the shading follows the basic contour of the head.
The camera makes the lines look kind of harsh, so it looks a little bit stringy, but this is the basic idea.
Note: the curlier the hair gets the more difficult this is. BUT, practice practice practice. I wish I could be a better help to you guys, but I'm just learning this technique myself. :/ but good luck!