I kind of made it up as I went.................I made the ruffle first, hemming the bottom edge of the fabric and machine finishing the other raw edge, so it wouldn't fray. Then I ran the gathering stitch that others talked about on here. Oh, and I sewed the sides of the fabric together so it was like a tube or a cuff. Gathered the fabric. I cut off about four inches from the bottom of the jeans. I then fit the gathered fabric to the jean and sewed it on.Then I placed the grosgrain ribbon over the top of the fabric, where it met the jeans, and stitched both edges of the ribbon (top and bottom) with a straight stitch. I used two strips of the grosgrain.
It was super simple, and I hope I explained it clearly. I made sure to finish all edges so fabric and denim wouldn't fray. And for the shirt, I sewed on the ribbon the same way. With the bows, again I made it up as I went, so it made sense to me. I put fraycheck on the ends of the ribbons for the bow so they won't unravel.