3. Build layers, (dark first, then medium, and highlights last) being sure to focus on contrast and value.
I could probably spend another 10 hours on the painting and still not be satisfied.
Notes to self:
1. Buy pastel pencils for detail work. It was very difficult refining the details of the face with my fat sticks.
2. Buy sand paper for sharpening sticks to make sharp edges for detail work.
3. Always have baby wipes on hand to clean hands. It's very annoying when you're working on highlights and you blend it with a dirty fingertip covered with black chalk.
4. Spend a little more time on the initial sketch, if you get the proportions wrong in the beginning it's hard to correct once you have layers of chalk on your surface.
5. Invest in a table top easel. It's easy to work in a vertical surface so the dust slides off you picture.
6. Know when to move on from your work, when the paper won't hold any more chalk.
7. Pick a simpler subject next time.