Jasmine asked me to explain how we made the sashes for her dresses. We found a champagne lace fabric and a matching chiffony like fabric in the special occasion section at Joanne Fabric and Crafts. We bought tons of it and used it all around the reception. (Of course we used a coupon.)
To make the sashes, we cut rectangles about 14 inches wide and the length the waist measurement plus a couple inches. (Obviously not an exact science here.) We folded the sash to make it about 4" wide. We tried to put in a pleat to make it look nicer. We ran a shallow seam along the ends to hold it pleated and hand stitched a few places in the middle. We sewed velcro on the ends for a fastener.
Jasmine determined how long she wanted the bow and the ribbons on the back. We lined the lace fabric with the chiffony fabric and folded it to 4" and sewed on the center band. We cut 4" wide strips of lace and chiffon and used the machine to stitch them together at the very edge.