They are all woven fabrics except for the black one, which is a knit. I finished the seams on the woven fabrics with a zig-zag stitch. 

On the smaller blue scrunchie, the white thread in the top-stitching stands out a little. So for the larger blue scrunchie and the corduroy scrunchie, I closed the hole with a ladder stitch instead of top stitching, so that the stitches are hidden. I definitely recommend this method to anyone else that doesn't have perfectly matching thread for their fabric and has the time and patience to hand-sew. 

Here are the dimensions I used:

Red gauze scrunchie (top left): "Jumbo" 7 x 34 (it's HUGE! How do I style it?)

Black scrunchie and larger blue scrunchie (top right and bottom left): 16.5 x 4 (I think these dimensions are my sweet spot for everyday ponytail scrunchies)

Smaller blue scrunchie (bottom center): "Classic" 16.5 x 3

Orange corduroy scrunchie (bottom right): 19 x 4.5 (I love how it looks but I realized as I was making it that the fabric is a little stiff for scrunchies. I think I prefer floppier fabrics for this application.)

These were a really fun, quick project. They are a great use for scrap fabric. The blue and black scrunchies are made from fabric I had leftover from dressmaking, and I'm really excited to have scrunchies that perfectly match my dresses!