Better Dunking, Palming the basketball
Palming the ball. Most of my friends say that you can’t do one-handed dunks without palming the ball unless you are tall enough. Not necessarily! Sure it helps if you can palm the ball. You have better control over the ball and thus you are more confident in your dunks. This is important too.
Dunking tip - Lick you fingertips for better palming.

But instead, you can do it this way. The next time you go for a one-handed dunk, catch the ball with two hands right before you jump. Bring it up as your body goes up after you jump.
As you extend your arms, turn away your left hand (if you are right handed which of course means you dunk with your right hand, if you are left handed turn away your right hand) and as soon as you reach that point slightly above the rim you can dunk the ball. Read that carefully.
For those of you with true passion for this game!
Let’s look at some ways you can do in-your-face-dunks. For doing in-your-face-dunks, it’s far easier if you can palm the ball. That’s for sure. Unless of course you want to dunk with both hands which is little harder to do because of two reasons.
You can’t jump as high. That’s a fact.
If you dunk with both hands the level where the ball is can never be higher than if you dunk with one hand. And..
When you go up with a palmed ball in one hand is very easy to extend your whole body to the MAX and thus hide the ball from the defender.
So if you decide to dunk in someone’s face with one hand you can do it this way. While you are going against the rim and you see that the defender is trying to block you, you simply put the arm that is not holding the ball (with your wrist pointing at the defender) in front of you so that he won’t be able to reject you that easy.
It really helps because this way you are in a better position.
You can even hide the ball by extending the arm that you are holding the ball with even further. And assuming that he is not really 10 inches higher than you and 2 times stronger, you should be able to DUNK IN HIS FACE Let him know who he is dealing with. It will scare him even more the next time he tries to reject you because subconsciously he knows that you’ve already dunked in his face.
Another way you can do it is, if you decide to dunk with two hands. This helps if you are not as tall as your defender but you are little stronger.
If you are somewhat stronger, you can do it because of your body. Your body will dominate in the air and it will push his body away thus getting you closer to the rim.
If you decide to go with two hands you should hide the ball by bringing it behind your head if you have the time to do that (meaning you have a decent vertical leap)
Now, there is another very important factor and that is the positioning. If the defender is ready to reject you (assuming he is as tall as you are, and has about the same vertical leap and is about as strong as you are) then it’s more difficult thing to do as opposed to if he was 2 seconds late, meaning you’ll be in a better position.