"But I can't jump like she can." Maybe you can.
Core improvement elements are:
- Skill
- Strategy
- Physicality
- Psychology
Establish your baseline then go to work.
Don't buy expensive equipment. Controlled jumping drills (you could use chalk lines or duct tape).
Change of direction half-circle drill.
Ten jumping drills (across sports).
Agility drills (volleyball emphasis but across sports)
Use chalk or tape lines and you can make "hurdles" out of bundled newspaper.
You won't magically become a better athlete. "Champions do extra."
After you've worked out three to four times a week for a month, repeat your vertical touch, broad jump, and three-cone time.
Lagniappe. A bonus from Alan Stein