I made a book cover from nappy liners. There was a workshop online using dryer sheets and not knowing quite what they were I decided to try nappy liners, which I thought might be similar. They aren't really, but they gave a nice result.
I put 3 liners together, having printed and painted some colour on them. They don't take colour so very well, but enough for the purpose. I then stitched them together onto a piece of felt, with free machine stitching all over. Then a little zap with a heat gun and a bit more stitching.
Then I neatened the edges, wrapped some cord by zigzagging over threads, and couched that down, leaving ends to wrap round a button to fasten and threaded on some of my paper beads to look decorative.The piece was just the size of the book opened out, so I had to attach separate panels to each side to make pockets into which the book covers could be pushed. The book happened to be one I had made, A5 size, but any could be used.
It feels nice to handle, and was easy to stitch, so is on the list of 'Try that again sometime' ideas.