By the way... You can sew ruffles onto cushions, blankets, blouses, dresses - anything you like!
1.Size/length of the ruffle: Measure the length of the edge onto which you wish to sew the ruffle. Multiply by 1.75. E.g. the edge measures 30 cm: 30 x 1.75 = 52.5 cm. 
2.Ruffle width: To make a ruffle with a folded edge (A), add 3 cm to the desired ruffle width (2 cm for the fold + 1 cm seam allowance). To make a ruffle on the fold (B), calculate 2 x the desired ruffle width + 2 cm seam allowance. Sew two parallel lines of gathering thread 0.5 cm from the edge. Use a long stitch length (preferably 5-6 mm). 
3.Hold the 2 upper threads and gather the ruffle to fit the edge of the fabric - in this case, 30 cm. Lay the ruffle onto the fabric right sides together. Sew along the raw edges (1 cm seam allowance). Overlock the edges. 
4.Press the seam allowance away from the ruffle and edge stitch from the right side to keep the seam allowance flat. 5.NB: You can cut your ruffle across the grain or along the selvedge. You may have to sew strips together to make the ruffle long enough (e.g. on a blanket).
