Download the Game.
Go out and find 3 friends.
1. Person needs his own IP
Make sure all are in the same network
1st Starts the game and connects as Host
2, 3 and 4 write the IP into the field and Connect as Client
find out who is which gunner / captain
drive out and shoot the enemy. If you run out of ammo, you can collect some.
Don´t forget to talk to each other, it Helps!