You must have your house meter full and flashing. The crowd must be chanting "Juice House, Juice House". Then hold L + R and press Y while running from the foul line towards the hoop in order to make a successful alley-oop and break down the goal along with the backboard, thus winning the game.

The first anwser is right, but with the created player you must be able to buy the ablility to do alli opps in order to bring down the house with a created player. Then when you buy that ability you will be able to do it the one the other has said.

Hold both juice buttons and then Y and if you don't have alley-oop you will automaticlly gain it.

you have to get 500,000 credits and then go buy ally oops then get a house meter get people chanting juice house press L+R Y then press B to catch the ball and it will go into slo-mo and bring down the hoop