I made this super simple ruffle strip bag recently. I love book bags. I carry them by the dozen. I also love whipping these sort of things up, they make great gift bags for gifts, or just great gifts. This is a really simple one. I had some scraps of fabric left over from other projects. The middle was about half an inch thinner than the outer strip I sewed the scraps I had together and made each of them one long strip. It was almost three times the length of the bag. I layered the first one in the middle of the larger piece, and pinned both to the top of the bag.
I set the needle at the top, and started squishing and sewing. The only difficult part is keeping it even down the bag, not that it matters that much to me. You could sew and ruffle it before you add it to the bag, pin it in place so it's straight and sew it to the bag, or you could go for broke and just run that needle down the bag....I live life on the edge.
I added a flower to the side with more scraps and now I'm ready to gift give.