Cheerleading tryouts!?

My God, I'm so excited! I'm trying out for the game team as JV or freshmen (they haven't decided if they're having a freshmen team yet). I just need tips from everything from moves to shoes. So I have a wide background in figure skating, dance and gymnastics. We have a 2 day cheer clinic where they teach us a cheer and dance and we perform it all in front of our judges (current varsity cheerleaders) on the third day. We need to also show 3 jumps and a "specialty move." My 3 jumps are my left hurdler, pike and toe touch, my hurdler being the best. My specialty move will be a front walkover into split. I also want to be a flyer but I won't be mentioning that at try-outs. I have a scorp, arabesque, heel stretch, front stretch, nike and bow and arrow. Problem is, I'm not a tumbler. Cheer is power, power, power while I'm all about grace. Hopefully my flexibility will compensate, what do you think? The packet said to wear black or blue shorts, a white t-shirt, no jewelry, tennis shoes and your hair in a neat high ponytail with a boy that they'll provide. I have THICK, curly, long hair. My hair barely stays in a ponytail for more than 5 minutes when doing gymnastics, tips for keeping my hair up? Also, tennis shoes! Should I wear my grey Vans or my Nikes? The Nikes are custom, deep blue and hot pink and say my name on them (Air Mogan 2.0s). Which should I wear? I'm veryyy loud and bubbly so the whole personality thing is no problem. Just tips on everything would be greatly appreciated! THANKS!!