Nothing. If it is cold, then I will wear a shirt, but that is on the top. Still nothing on the bottom. I do have a bathroom connected to the bedroom, so that makes it easier, but I would probably do the same if I didn't. I would just need to remember to cover with something while out of the bedroom, unless I was around others who are not bothered by nudity.
I used to wear nothing then I had a nightmare about a spider crawling into my vagina during my sleep, laying eggs, and me waking up to about 50 spider babies popping out of my coochie kingdom. It was traumatic. Now, I will not wear nothing unless I have bombed the apartment with spider foggers. I'll typically wear undies, satin shorts, or rayon shorts with no undies.