I'm sure that you'll learn the basics of the game during the tryout. But if that doesn't convince you enough, then just know these simple rules. 1. Ball can only be passed backwards and laterally (to the side). A forward pass is an infringement. 2. You can only tackle the man carrying the ball. Tackling someone without the ball is a big no-no. 3. If you drop the ball forward (ex: it slipped out of your hands and touches the ground in front of you, not behind you), also known as a knock-on or a fumble, it's an infringement. 4. You must be behind the ball carrier (your teammate) or you'll be offside (but it doesn't mean much if you don't participate in any play and/or you move back to onside). Those are some of the basics. Also, I advice you to work on your cardio. Try doing this:
You learn by playing and watching