How can you jump higher so that you can dunk a basketball?

when spud webb at 5'7 won the nba slam dunk contest, that gave me a dream to dunk too. looking at spud webb, he is relatively short in nba measurements, but he compensated his shortness in his ability to leap high to be able to dunk. and two years ago, another non-6 footer won the nba slam dunk constest by the name of nate robinson. he stands 5'11. anyway, some high jumpers put weight wrapped around their shin. then they keep on jumping. i believe jumping high can be achieved with constant practice and right body-built. i have seen the two slam dunk champinos; their bodies are not that "heavy." keep jumping, keep reaching the sky; it is never impossible. think spud, think nate.