Human: Don't drive the warthog/prowler. Be the turreter! More kills = more points = closer to winning the game! BR's (battle rifles) are scattered around the map, as most INFECTION games, zombies have 10% health one shot aimed at a ZOMBIES head with a BR, will result in a kill. Ghosts are great for humans as they have boost - guns - and great traction.
Zombie: If you see a person alone walking around killing zombies with assualt rifle, circle him! he cant take his eye off you, which either aother zombie can come get him or, he'll try shotting you. When he relaods go at him! And at the start of every match (if your the Alpha Zombie) go straight for the vehicls 80% of human starters head for the vehicles.