Protocol
When a free kick is paid, the player's opponent stands the mark, by standing on the spot where the umpire indicates that the free kick was paid or mark was taken. The player with the ball then retreats backwards so that the ball can be kicked over the player standing the mark; the player must retreat on the angle such that he, the man on the mark and the centre of the attacking goal are in the same straight line.
A player receiving a free kick is not restricted to kicking the ball; he can play on by handballing to another player, or run around the mark where the free kick has been paid.
Read more about this topic: Free Kick (Australian Rules Football)