I recently made a yoga mat for my mother in law using cotton poplin, burlap fabric and polyester batting.
It was an easy sew. I just used a precut polyester batting piece which was about 1.25 mts x 90 cms. I cut the top fabric to almost this size. My batting was slightly larger than the top fabric. Since this was a yoga mat I needed fabric with some grip for the backing. All I could find was some burlap. So used that. I used about 1 mtr of burlap. It was slightly smaller than the batting. So I pieced a strip of the top fabric to both the sides of the burlap.
Then I sandwiched all three together using a lot of quilting pins and just quilted using a walking foot in a grid pattern.
I made a couple of ties for tying the yoga mat for easy storage when not in use. Then I basted the strips of this to one of the short edges and then used 2.5″ wide strips for binding it using my machine.