*volleyball* How can I improve my jump in 2 months?

I had to quit my club team because my coach was horrible, and her daughter was on the team and her daughter was horrible and i played the same position as her daughter. so now i am just practicing with another team and next year i have freshman (high school) tryouts and im only 5'3 and im a good setter, and i can jump to 8'5. i really need to improve my vertical please help!