i'm relatively new to this, but i think i can help you out. you corn-row wet hair,let it airdry and then take it down. depending on how you braided, you will have waves or "crimps". there is another thread that describes it. do a search. find peachtree. she actually has pictures of this technique.
By using plaits, braids or cornrows on wet or dry hair. You'll get waves (tight or loose). I used to do this a long time ago on my blow-dried relaxed hair. The waves would last until my next shampoo (one week) and get looser each day.