I have a tub of old denim jeans that I've dug into over the years to make some blue jean quilts. And I've been making a lot of flannel self-binding baby blankets the past couple of years and that resulted in flannel scraps. So what am I doing with them? I'm making a rag quilt.
First I've cut a lot of 6.5" squares of denim and of flannel. From smaller scraps I've cut 6.5" x 3.5" bricks of both. Next step is to sew a flannel piece to a denim piece using diagonal lines from corner to corner, both directions, making a big X on each block.
Then I'm sewing them together with the denim sides together. And the resulting seams are clipped toward the seam line about every half inch. Once the rows are sewn together to make a quilt, and it's washed and dried, then it will end up with fluffy frayed seams all over the flannel side.
This project is kind of like my string blocks - I make a few at a time when I'm in between projects and just want to do a little sewing. And slowly these will become a kid sized quilt.