Hi Ruthe,
One more piece of input from a 19 owner and a sailboater. I use a good cotton topped mattress cover with deep sides. Wish somebody made colored mattress covers! The bed is 8 inches deep and if I buy a mattress cover for a 12" or 14" deep queen mattress it works to center the quilting, cover the mattress, and usually stays on if I am careful when I pull off the sheets to launder them.
Next I use stretchy flannel fitted sheet for a queen size deeper mattress. So comfy and stays pretty well stretched. Yes, you must lift the heavy inner mattress corners(one at a time) somehow

to get the fitted corners in place-so while I'm there lifting the inside bottom I also tuck in the corner of the top sheet and a bit of our blanket.
On the non-fitted top sheet, I use cotton unless cold enough for flannel, I have sewn a 12" wide 3' long extra piece of sheet and tuck only that piece at the foot to leave the top sheet loose for foot movement.
"Making the bed" to tidy up just means smoothing the bottom, pulling the sheet up, then the blanket. We like fleece-king size blanket, very light weight.
Works for us.
But I have a question. I'm too cheap to buy sheets to try them. Are there any comments people want to make on the comfort of synthetic blend sheets?
Sea Star -Kathy