Cut your scrap fabric to measure 4” wide by 18” long.
Next, fold the fabric in half width wise with RIGHT sides together. Using a sewing machine set to single needle stitch, sew along the cut edge with a 1/4” seam allowance.
Start sewing 1” from the end and continue until you’re 1” from the end. Reinforce your stitches at the start and end with back stitching.
Turn the piece RIGHT side out.
Match the short ends with RIGHT sides of the fabric together. Sew the ends together with a ¼” seam allowance. This will complete the scrunchie piece leaving about an 1 1/2" opening for the elastic to be inserted.
Cut flat elastic to 8” long.
Secure a safety pin to one end of the cut flat elastic. Guide the safety pin into the unstitching opening and pull it through until the exits out the other end.
Knot the ends together.
Extend the scrunchie forcing the elastic inside. Using a sewing machine, sew the opening closed along the folded edges.