How can i become a better cheerleader?

i'm gonna be trying out for cheerleading in a little after a month and i really want to make it! i'm gonna be a freshman and for tryouts you have to know a double toe touch, pike, and tumbling. i already have a little tumbling down but i need help getting better at jumps. how can i improve them??? also, is there anything you recommend i work on? thanks a tonn! (: