everything off, semi-dark.
I go to bed around 6 am, as the sun is starting to rise, and the windows in my bedroom face the east. unless I'm in bed before 5 am, it's never pitch black. plus my street is kinda noisey, even at night.
after living in college dorms, though, I'm able to sleep through just about anything if I have to.
I can understand the fan, though. at the end of every summer, I get so accustomed to the white noise of having my AC on all night that it seems strange those first couple nights for the room to be so silent.
one of my roommate's in college had to have music playing whenever he went to bed. it was the most bothersome thing ever. he listened to crappy music, frequently left it on repeat so it'd be playing all night, and would immediately wake up if it was turned off :Q