1/ Create a co-op survival room.
2/ Start the hack as Admin
3/ Start the game.
4/ In-game, just when the enemy soldiers appear, Press Enter in the chatbox writen "Box: 3". Do it quickly because in other case, they will kill you.
5/ Back in the room, start again. You'll see that soldiers will start to die.
6/ Now, write in-game "AutoStart: 1" to activate the AFK-Mode.