I have a couple things that really help. I rarely get cramps any more.
1. About 4 days before my period i start taking an Aleve type of medication twice a day
2. I regulary take magnesium supplements.

The magnesium apparently helps relax muscles. Taking a painkiller a few days before hand helps it build up in your system so it can help better when the pain starts. On the day of the cramps i use a heating pad if i need to. I rarely feel crampy any more.