omg...I really want to try reining too!!! But, I don't have a horse, and I need a trainer that's kinda close to me. But, yeah...I really want to try reining-it looks so fun, and it's amazing to watch. Especially Stacey Westfall's bareback-bridleless ride!!! So, unfortunately I can't help you with what to work on before you start...as I don't even rein, but I would say do lots of transitions, circles etc. And, let me know how it goes, 'cause I really want to do it too!
Horses...what would we do without them???