When I hiked the Pacific Crest Trail (3000 miles, 6 months or so) I had no pillow or bed. Just a 3/8" closed-cell foam pad on the ground and a sleeping quilt (bottomless down sleeping bag). I did not dig out a hip hole or arrange my things to form a bed or anything. I would attempt to raise my feet or knees but whatever I used would eventually move or flatten. Sometimes I would use my paperback book as a pillow, but I didn't always have one and it usually got moved out of the way at some point in the night if I did. It took a while, but I figured out how to sleep on my side without a pillow. I had to arrange my hips just so and I usually put my hands under my cheeks, prayer-style. Mostly I slept on my back because it was the only position where I wouldn't drool all over everything. Drooling onto closed cell foam or nylon fabric and down is really unpleasant. The worst is when the drool actually pools in the corners of my eyes. Don't know nothing about apnea but lots of problems with drool. I use a pillow now at home mostly for drool. Sorry that's so gross, but if you know how to stop the drooling, please let me know. It's been a life-long bother.
Female, 5'3", 50, Max squat: 202.5lbs. Max deadlift: 225 x 3.