For me sort of depends:
Summer - hot nights, I just sleep with only shorts, nothing else, no covers, and the fan on either low or medium. Stuffed Cheetah next to me
Winter - cold or snowy nights, I sleep with warm clothing, pants-long sleeve shirt. I might turn on the heater for a few minutes until blankets warm up if the temperature is too cold. Stuffed Cheetah always with me.
Spring and Autumn - typical rains, if its not too cold I will sleep with only shorts, if its a bit to on the cooler side I will put on a t-shirt. Stuffed Cheetah next to my head. I have nightmares if the toy is not next to me at nights
I always keep my sandals on one side of the bed, in case I need a drink of water or need to the restroom. My room has to be pitched-black for me to sleep well. If I'm falling asleep any light source will bother me and take away the sleepy feeling. After sleeping for hours even light won't bother me - I will fall asleep again.
My sleep pattern is way off - I sleep for about 9 hours from 3:30am to 12:30pm. Days I need to wake up earlier I will try and fall asleep earlier usually I never succeed, and sleep less than 6 hours, after getting back home from where ever I need to go I take a long nap.
The worst sleeps I have is when I have the common cold. No matter what position I get, 5 minutes later one side of my nose will get stuffed, I switch over and 5 minutes after getting comfy my other side of the nose gets stuffed.
Sleeping position: On my back, or on my side, one leg over the other. One arm near my head, and the other wrapped around the stuffed-toy cheetah. This is the reason that in the mornings I can't find the tv remote, I kicked on the floor.