If you hear shots, running away from the action is the safest option. The farther away, the better, as a shooter’s aim decreases with distance. If running isn’t possible, hiding is the next-best option. Be sure to hide outside the shooter’s line of sight. And if all else fails, fight the shooter using found objects or by attacking him as a group.
Some experts say the advice to “hide” is too simplistic. Instead of hiding anywhere, like under a desk, experts say you should barricade yourself in a room to try to deny entry to a shooter
Kneel with your Bulletproof Back pack on your back.
Place your Bulletproof Back Pack in front of you.
Lay down on the floor directly behind the Bulletproof Back Pack