How do you get a proper hand grip when dunking a basketball?

I'm trying to dunk at a 10 ft. basketball net but I always lose my grip of the basketball when I'm at the rim. I tried to put my hand under the ball instead but my posture is awkward. I want to do a one-hander first (while running). Any tips?|||Yea there really isnt a trick to it, you just need to be able to grip it well which requires appropriate pal size. But there is a trick, once you get levitated, if you can try and roll the ball with your tips to get the ball at a downward angle that way, the dunk even if you cant hold the ball it should still slam down in the hoop.|||If you can't palm the basketball, your hand isn't big enough to support a one-handed dunk.