Start with a ping-pong ball, then a tennis ball, then a softball, then a volleyball, then a youth-sized basketball, and on up until you can dunk with a regulation size ball. If you can't palm the ball, then you will need to learn how to control the ball with two hands until the last minute extension for the dunk with one hand, or you will have to jump high enough to dunk two-handed.
This is a dunk where the player takes off from a distance which is significantly further away from the basket than is considered typical. The free-throw line is most commonly constituted as the take-off point, an effect likely attributed to the easily observable span between the line and the basket in the view of the TV audience. In order to achieve the hang-time and altitude necessary, players will generally leap from one-foot to maximize the momentum generated from the half-court running start often required to complete the dunk. A cornerstone of dunk contests, dunks from a distance are also performed in games, most often on the fast break.
Which is why, on April 1, 2014, I dedicated myself to dunking a basketball for the first time. So that I could live it, breathe it, perhaps take a crack at it with my pen. I had tossed this idea around for years, realizing with each passing birthday that my chances of success were dimming. However, on that April Fool’s Day (a coincidence) I spent three hours on the court and at the gym, with a promise to myself to return several times each week until I threw one down like Gerald Green. Or at least like Litterial Green, who played in 148 NBA games between 1992 and ’99, and who, like me, was born in the early ’70s, stands 6'1", 185 pounds and is at no risk of having dunker carved into his epitaph.
The simplest method to measure an athlete's vertical jump is to get the athlete to reach up against a flat wall, with a flat surface under his/her feet (such as a gym floor or concrete) and record the highest point he/she can reach flat-footed (the height of this point from the ground is referred to as "standing reach"); fingertips powdered with chalk can facilitate the determination of points touched on the wall. The athlete then makes an effort to jump up with the goal of touching the highest point on the wall that he or she can reach; the athlete can perform these jumps as many times as needed. The height of the highest point the athlete touches is recorded. The difference between this height and the standing reach is the athlete's vertical jump.