I have really erratic sleep habits. Sometimes I'm tired by mid-evening, other times I'll sit around until it's daylight and still not be tired. Usually I just happily sleep in my bed, sometimes on the sofa. Generally I have the window open, and the curtains open just a crack - the idea being that it's more daylight when I wake up, so that I stand more chance of actually getting up instead of going back to sleep. Never works, but it's habit now.
Sometimes, if I'm having trouble drifting off, I'll put music on. It has to be instrumental though, which tends to mean post-rock. Last time I fell asleep to music with vocals, my subconscious took hold of the words and inserted them into my dreams in random order. A whole night of dreams as scripted by a random text generator is not something I ever want to repeat.