I like to look back at old sketchbooks and see how much I have improved/ learned over time. I like to take the same sketch and re-draw it to see how I would do it differently now. So in January I went back to September's sketchbook and re-drew a few sketches. Today (in May) I went back and drew them a third time. It's pretty cool to see them all together and see how I have (in my opinion) improved a ton. I have to admit that the earlier sketches make me feel embarrassed. I obviously needed more practice, so I have spent the last few months filling up sketchbooks full of heads since I really wanted to get more comfortable with drawing them. It's really helped me and it's neat to see how my style is forming.