The unofficial rules of escaping zombies...
1) Don't move. That "safe place" you've been told about 50 times that's several miles (and a zillion zombies) away will be way overrun before you get there, to the surprise of your entire team (despite the fact that millions of others were told to flock there and most of them would have become zombies eventually).
2) If you do move, don't faff about. Although there are some great improvised weapons, nothing quite beats a few lorries moving at high speed all together as a team. Weapons are your backup for when the fuel runs out in every single vehicle.
3) If you can't get away safely, find a huge, big solid wall, find a decent corner with another huge, big solid wall and camp in it. There's always one somewhere. Do not use plasterboard walls.
4) Check the roof, and the floor. Nothing more embarrassing than being dropped on or tunnelled under when you're in an otherwise safe place.
5) Chokepoints. Don't stay in a room with eighteen doors and windows. One. Your escape route will be overrun too when you least expect it so don't bother with an emergency exit - one doorway, let them come at you over the heaps of furniture while you all aim everything you have at them.
6) If ANYONE in your group acts weird, shoot them instantly, and then shoot them again to make sure.
7) Don't worry about the miniscule risk of hitting an innocent civilian or helpful health carrier amongst the horde. They were going to die anyway.
8) Don't rely on the Army, Navy, Air Force, National Guard, Police or anybody else to help. They won't. All they will do is produce an endless supply of heavily-armoured zombies.
9) Be suspicious of every new recruit - put them in a quarantine group basically-forever and don't let them near the group you KNOW isn't infected.
10) Expect someone completely at random to get infected.