I searched around for some vertical programs that actually worked for people. So i found these unintentionally. Sites like these, I have never found before and if i did, my jumping would be much better already. I don't want to have to pay for some jumping manual for $500. Somehow, I found a site with exerises to increase your vertical, right on the front page. So I don't have to list the sites, I will show you the stuff I found right here.
First exercise I want to show is: The Raise of the Cavaliers. In this excercise, you place your toes at the end of a raised stabilized surface such as the stairs. You lift yourself up only using your cavs. Strengthening these muscles help you quickjump on the spot. Do 3 sets of these until it burninates. This exercise won't cause injuries unless you lean back and fall down the staircase.
The 2nd exercise I'd like to show you is incredibly important; the Quadrecep Leap-ups. Here, you squat halfway down and jump as high as possible. As you feel the burninating of the quadreceps, the exercise is working.Do 2 sets of 20 to 25.
The 3rd exercise is one-legged jumps. You need a sturdy chair for this. And James , don't break the chair. Put one leg on the ground and the other on the chair. Then you leap up using only the leg on the chair. Switch legs each time. Do 2 sets of 15.
The last exercise is the continuous jumping (for 2 times). You jump as high as possible and right when you reach the ground, you jump again. DO NOT BEND YOUR KNEES! Do 2 sets of 15.
Sources below:
5 days a week and the vertical shall add up! Motivating Song (You and James'll like it)
Have fun with these Art!