I think they suggest on your side is best. I am a "back" sleeper so I try to keep my head/shoulders elevated. Sometimes I get tangled up in my O2 tubing and that usually wakes me up. 😆

I have a wedge on my bed that keeps my torso slightly elevated

If you're consistently waking up during the night, I'd suggest that you have a sleep study to help you figure out why you're waking up all the time.

We have a split king adjustable bed. So I can elevate without my husband having to. I sleep with it fully in the upright position. I sleep all night and I am not on oxygen while sleeping