I think making them with a ruffle foot is the best way really. But, I saw an episode of "Sewing with Nancy" that she used a string and zig zig method that I have used too. I think many of her shows are on her site, so maybe you could watch it? I am sure utube.com would have a demo you could watch. They have many sewing shorts that you could check out. Sorry I could not be of more help. But that gives you a starting point if you want to go searching a little to find a video.