The sofa bed in the living room isn't particularly comfortable, but it is also not used very often particularly now I have a guest bed in the study/guest room.
However I thought I would try to make it a bit more comfortable when it does get used.
I took a thin mattress topper and a spare summer weight duvet. I cut and pieced the duvet so it was the same shape and size as the mattress topper and then sewed them together with a zigzag stitch all around the edges.
I must admit managing all that wadding under the sewing machine needle was really quite a challenge, and I am super impressed now at anyone who makes quilts.