Please give advice and critique

[Maurice]

When doing a "study" (I don't know if I could call what i'm doing that) I always do it the same way, some circles and lines, and then putting stuff on top. All eye-balled. I think I've learned a few things from it, but like you said i'm not getting much bang for my buck. With head studies and stuff like that, should I try doing it from my imagination, or by using a photo? If I don't reference anything, how will I know if i'm getting the placement right? Also, people seem to use boxes a lot, would that benefit me?