For me - no alcohol, no drugs, only one cup of leaded in the morning. No sweets after 3pm. Low carb, high protein. I'm on a huge vitamin regimen too. I also cut out migraine triggers: chocolate, yogurt, almonds, cheese, avocados, MSG (I found it in Adobo Seasoning!)
Sleep is a big one for me. I know, it's 12:37am Chicago time. (it's finals week, ugh!) I'm super stressed!!!