Well, I begin under everything, sheet, blanket, spread etc. But as the night goes on I must kick everything off. I wake up with all covers balled up on the floor.
I sleep under a sheet if its hot, and add a blanket or two if its cooler. I used to have an electric blanket when I was younger and lived in a colder climate, but I never get that cold anymore.
Always sheets (nothing better than high thread count, crisp sheets!), and several cotton blankets. I love the weight, but hate being too warm. I keep the house quite cold year round, so I don't change much from summer to winter.
We have sheets, a white thermal-ish blanket (easily bleached), and then a down duvet insert with cover. It gets hot if we don't keep the house pretty cool, but I have to have a lot of weight on me or I can't sleep. Sometimes in the summer we will replace the down duvet insert with a cheap, thin, Walmart comforter. A lot cooler that way.
I HAVE to sleep with a sheet, blanket, and comforter! Even though I live in Memphis, and even though I'm hot natured, I just can't sleep well without being bundled up