itch.io

You can to not  look at freddy. She laughs 5 times, and 5 time is 4-5 am. So when freddy laughs 5 times after about a minute she will come. So keep the door open for 30  seconds after 5 laugh and close it.

TIPS:

Keep the camera on Foxy's cove (cam 1C) the entire night (until Freddy laughs 5 times) and spam cams, like a lot. while spamming the cams listen for footsteps at the doors, when you hear foot steps check a door and if no one's there, immediately close the other door. after about 4 camera flips (2 cam flips on 4/20) open the door or check with lights first. (If you didn't already use lights and see them on the door you know they're at, when you do use lights it will make a sound if they are still there)

When foxy disappears from the cove, don't check the hallway cam to trigger her run, instead wait in your office and hold your cursor on the left door button, when you hear 3 quick footsteps close it quick. This will save some power. 

After you hear 5 Freddy laughs (around 4 or 5 am) then switch the camera to right door kitchen (cam 6) where Freddy should be. This helps because you don't actually have to be on Foxy's cam (cam 1C) to stall her and only have to be on cams in general. 

If you're on Freddy's cam, (cam 6) she can't kill you, like at all. and if you want to check Foxy to see if she will be running to your office soon, close right door, quickly switch to Foxy's cam, quickly switch back to Freddy, and then open right door and keep spamming cams (or get ready on left door if Foxy's coming). This way you don't waste power with right door closed for like an hour.

Make sure that after the sixth Freddy laugh, (when she goes away) you go back to watching Foxy, just to be safe

This is how I beat 4/20 mode and it took a couple tries because of RNG on how quick Foxy gets out and how quick Freddy gets you when out of power. I won while out of power after her song finished and it was very close, so don't be suprised if it takes a few tries. Or maybe I just suck