Proboly everyone already beat night 6 but if you didn't here a really easy guide to beat it

Keep check cams 3 and 4, if you see Hourglass at this cameras turn off a random camera (besides 3 and 4). Also, if hourglass appears at cam 3 they won't appears there twice IN A ROW

if don't see it on these cameras, turn out the lights AND stand still

Turn off the lights sometimes, even if Hourglass isn't in the room (to save energy)

Do it until the nights end, then rush your way to the third floor (use the flashlight, if you see The Face) put the code and -BAAM- you beat it