The writing process is an iterative one; you make something, revise it, and do it again. I've demonstrated this by taking a "snapshot" of an essay at every step of the way, from outline to final draft. Read through these example essays to see what kinds of changes I make between drafts.
After finishing a draft, it is a good idea to at least evaluate your own work; if you can get someone, like a friend, teacher, or parent, to do it too, that's even better. Use the "Outline Evaluation" for your Outline, and then just use the "Report Evaluation" for your 1st, 2nd, and Final Draft.