Use light to direct what you want the audience to look. Generally, where there is light there is safety. If you can see it, it's usually not scary. A brightly lit room is not as scary as a dimly or sparsely lit room. Think of a campfire. Those around a campfire feel safe, perhaps more safe than they should, because all around them is blackness which could hold untold evils. That said, some rooms can be too brightly lit. This misdirection can be made more scary if the audience thinks there might be something wrong with the perceived safety of the scene. Watch the dining table scene in Alien for a brightly lit scary scene.

This is such a broad question. Watch movies you like and copy the lighting. But be aware of the nuances of the scene and use them. There is a lot of mis-direction (like a magician) in good horror movies, either making the audience feel scared when there is nothing scary about to happen, or feel relaxed when someone is about to die (the old cat cliche, where someone hears a noise, thinks it's a scary murderer-guy and then relaxes when they find their cat Fluffy was in the garbage covers both these instances... if they get attacked while petting Fluffy and breathing a sigh of relief).

"On a good gate, that's a wrap."

I don't know too much about lighting because most of what I've shot so far has been on location. But lately, a lot of scary movies that have been released recently have had a lot of greenish/yellow lighting. Florescent lighting is kinda scary too in some applications. Make a lot of dark corners and places that people's eyes will be drawn to here and there.

Low angle lighting is a characteristis of horror films.