Play as a football player or a soldier with a rifle...it's anyone's guess really. Try to shoot the red team before they can murder you and take their money. You'll want that so you can pummel them harder the next round.

Arrow keys or WASD to move. Lift click to shoot. If you start collecting cash you can upgrade to better weapons and better armor and also buy more ammo, which you're going to want.

The more ammo you can get and the better armor you can get, the better. Try to be dodgy enough that they can't shoot you and aim well enough that you land more shots than they do. Basically the strategy to every shooter game.