I feel like I used to have a satisfactory layout for years but haven’t since found a consistently comfortable arrangement. I like to have a fairly thick pillow or two under my head to accommodate my bad shoulder, a pillow between my thighs to avoid chafed skin, and a pillow for hugging - also mostly for my shoulder.
The head ones tend to get distorted really quickly and it’s really difficult to find a good hugging pillow.
I use a bath towel folded twice the short way. Nice and flat for back sleeping. I can make it thicker for side sleeping by folding the end under as needed when I roll over. But I use a CPAP so I don’t roll much at all.
Interesting, I don’t think I’ve encountered someone using a towel long term.
I use a CPAP, too, but toss and turn so much that I think the arm flick to adjust the air hose during the turn has become reflexive.