Developer's guide to surviving the nights! Spoilers obviously so if you want a challenge and to learn the mechanics on your own, stay away!
Night one is pretty simple - there isn't really even a reason to leave the bedrooms. You just want to move from window to window, looking out for the zombies and killing them.
It only takes 2 headshots to drop one so be patient with your aiming.
This night introduces a new threat, the Lurker. He's not too much of a hassle if you're listening carefully. If you hear the dresser in the hall scraping against the floor, investigate it immediately and hold E on it to put it back into place.
If the Lurker does manage to get in, it's almost certain death - however, you can dispatch it with 3 bullets but it is an incredibly fast enemy and very difficult to hit. Like the zombies, it's best if it doesn't get in at all.
Here is where things really start to get tricky. You're introduced to the "Roamer" which will occasionally try to get into your room. Keep your bedroom door shut!
If you hear the Roamer banging on your room, turn out the bedroom lights (both of them) and hide in the side room (the one with only one window).
He'll bang on the door a few times and you'll hear the door open. Wait a few seconds and you'll hear his footsteps walking away. At that point, you're now safe - turn the lights back on and shut the door.
Now is when all hell breaks loose. The Spectre has been around since night one but only gets you if you're in the darkness for too long. Now it's trying to actively force you to be in the darkness by shutting off the power.
If the Spectre forces the electricity to be overloaded, you must run to the generator to restart it.
Keep your flashlight's batteries charged or you will not last long!