Instead of copying the ENTIRE Pro-bending guide provided by the wiki, which is extremely detailed, we're just going to link to the official page.
PRO-BENDING GUIDE!The only adjustment we're makeing is incluing Airbending rules for the game, because we have a significant number of Airbenders, and excluding them for no reason is unfair.
AIRBENDING RULES
Each airblast cannot exceed one second in duration, meaning that airbenders may not use any form of a constant blast of air against their opponents. Air cannot be used to control or enhance the power of any other element. Airbenders cannot attempt to rescue teamates that have been legally knocked off the field before they hit the water, or else they will be disqualified. Airbenders are allowed to aim for the head.
Beyond this addition, all rules still stand. Teams are still comprised of 3 benders, however you may have an airbender on your team instead of any of the other basic arts.