I fall asleep on my stomach/side with my arm under my pillow, which is basically the worst position to sleep in in terms of spinal/neck health. But it's what I grew up doing and I can't fall asleep any other way unless I haven't slept in >24 hours :/
I generally wake up in any random position. I've been told by my wife that I turn around like 150 times per night, and I believe it. When I was single my sheets would generally end up either on the floor. tangled around my body, or scrunched into a corner of the bed.
Yeah, I'm a heavy sleeper. I wake up feeling very rested, though
