Hit "Z" nad "X" KEYS repeatedly as quickly as possible to gain more speed. Then press SPACEBAR to release your kick. Watch the angle of your kick.
The aim of this game is to kick the Ref as far as you can across the pitch.
When Ubisoft showed off Ghost Recon Advanced Warfighter earlier this month, we weren't allowed to talk about the multiplayer section of the game at that time. Now we can, and Ubisoft and its Red Storm studio (which is developing the multiplayer section) have clearly thought about what players liked about the original GRAW's multiplayer, because they have built upon it considerably.