Remember to train explosively for explosive gains!
Ankle weights will work. but can create small tears in the knees smaller ligaments.

Do 10 x 20 reps of rim jumps or trying to dunk in them, or touching the backboard.

Then jump rope in them for 10 minutes adding 2 minutes each week on your tippy toes after the rim jumps, each night.

Doing this program you can gain big inches to your vertical jump, but the gains are only tempory or as long as your using them. The gains would take about 2 weeks to start decresing again.