Basically one person starts as a zombie and must knife the humans but the humans are allowed to shout the zombie with a pistol to start off and the humans must switch and knife if a zombie gets them. At the end of each game your points from the game are added to your clan tag and thats where you store all of your points. There would usually be a point system on the post you got the lobby from saying how much points a kill is and an assist and then if you want to buy a gun you take away the cost of it from your clan tag. The prices should also be on the post. Usually humans are only allowed a certain amount of time in one camping spot though to give the zombies a chance to get them while they move. Hope i helped