I found 3 helpful glitches:

[kalczukipies]

1. In the garage, if you lower the board before the door closes fully (in the gas room), the granny will be locked there until we die.
2. In the attic, if the "boards" in the hole are damaged in a good way (one board on the right side from the side of the room with the mannequin will still be in place), if you go through it in the right way (keeping as close to the threshold as possible), you can go to the prison without using hammer.
3. Speaking of prison, if you go in and the camera catches you, you can hide behind a chair and then the prisoner won't see you.
I hope I helped and thanks to me you will beat the game or make it easier for yourself. Regards

[jmiller_2002_22]

You can also throw items through the boards in the attic and then hide in the box and granny will run through them and knock down the boards without using a hammer and if you lure granny to the attic and spray her with pepper spray and then walk through the hole in the floor and kill you self when you respawn she cant see or kill you but watch out for bear traps because if you step on one and she gets to you before you get out of it she will push you off the bear trap softlocking you and forcing you to restart