For me I think the most important (and most difficult) thing was honesty. Being totally honest with myself. Discovering why I behaved the way I did, and actively trying to change it. A good counselor really helped with this and helped me get below the 'surface' of why I reacted the way I did.
I've also read a lot of books. I moved on from the 'self-help' type to the more spiritual, self-awareness type. The Power of Now, and Women Who Run with the Wolves, for example.
It also helps to do things that make me feel good. I took a ballroom dance class last spring and a writing class at the college this fall. Finding time to just get quiet and be with myself has also been very beneficial.
L