The process is mainly listening for the girls coming to a door and not using the light, for foxy just check cams every few seconds and when Freddy gets to the marshmallow's you need to close the door a little before she gets to it.
Viewing post in (18+) Five Nights at FuzzBoob's: Definitive Edition comments
Foxy - Likes attention, and will run to your left office door.
Freddy - Giggles 5 times, as she moves, and then approaches your right door in the kitchen.
Chica - has a random path and will approach your right door.
Bonnie - has a random path and will approach your left door.
Try to stall Foxy as much as possible by keeping a watch on her on cam, constantly, because she loves attention.
For the other girls, you can only listen for their sound cues. So after hearing 5 giggles from Freddy, close your right door.
Bonnie and Chica make footsteps when they come to your door, so just close the appropriate door.