problem with alley-oop

i cant make it...what i have to do for an alley oop for dunk contest?

Go to dunk school and just keep practising. After mastering the standard of the backboard dunk you can do stuff such as throwing a ball of the shot clock then doing a front flip and putting the ball through your legs. Just practise the timing.

Yea you need to practice alot
When you get all that down pat then check out the dunk contest thread and there are all sorts of lob dunks and regular dunks in there