The rules to this game will mainly be rules for college campus grounds.
I have just recently heard about this last semester so I am not too keen on the details, but here it goes. You have to gather up a lot of people for this game. You have a selected amount of people be the zombies while the rest are humans. The boundaries for the game is within the campus grounds, so humans and zombies can "fight" each other in the dorms, school buildings, quad, where ever as long as its within the campus.
Well anyways, as for the rules, you have the zombies try to attack the humans thus turning them into zombies themselves, while the humans defend themselves from the swarms of zombies. Weapons for the humans are...socks? At least I heard it was balls of socks, it will probably be better with nerf guns or something, but they cost a lot of money so I would not recommend it. Zombies, I guess are left barehanded, my guess is that they will have to touch the humans. Also if the zombies get hit by the socks, they are to be incapacitated for a few hours, I think. You can probably make up this part yourself later on.
Anyways, the zombies are able to attack the humans at just about anywhere except for these designated places: Inside a person's room, inside the classroom, the cafeteria, and inside the bathroom. But zombies can wait outside by the door until they come out. Once a zombie "kills" a human, the human is "dead" or at least out of the game until a full 24 hours and then he or she will then turn into a zombie. You can choose to have the game end when all of the humans are zombified, a lone human is standing, or see whether or not the humans can outlast the zombie attack within a time period. The time period can be of any choosing, from a week's time to a month, maybe a whole semester or year. The choice is up to you. Just try not to make too much trouble with the faculty and staff when playing this game, they can be jerks when they feel like it.
You may want to make a facebook group if you ever create this game. You should make sure that you have each zombie and human player posting whether they have zombified a human or stopped a zombie. This will other players know who to avoid and who to help within the game.