To air dodge, simply press the L- or R-trigger while you are in the air. This move has changed significantly between Melee and Brawl.

First, characters can no longer air dodge at an angle using the control stick. Instead, the direction of the air dodge is usually stationary, but the little movement that does occur is due to the momentum prior to the dodge. While wavedashing can no longer be performed in Brawl, it is possible to waveland by simply dodging near the ground before your character lands from a jump, the momentum from falling will transfer to the air dodge, which will in turn transfer to the ground and create a small sliding animation.

Second, all characters can air dodge multiple times while in the air. After air dodging, your character has a brief recovery period, after which it is possible to simply air dodge again. This little change between Melee and Brawl has big implications. It’s possible to air dodge out of just about every scenario and combo with little risk, so do so often. Air dodges have a very small window of vulnerability at the end of the dodge; make sure to time the air dodge as perfectly as possibly to avoid being hit at the end of the dodge.

A final tidbit on air dodging is that it reduces momentum. All attacks in Brawl have very little hit-stun, but reduced hit-stun doesn’t mean the momentum from an attack ceases, it simply means your character is able to respond while it’s flying in the air towards certain death. Yet, there is beauty in all this, since characters can now air dodge just after receiving a hit, allowing momentum to be reduced substantially. Get in the habit of air dodging just after a powerful attack so that the distance your character is sent is reduced.