Hello. I use a casing, which is a seperate tube of fabric sewn to the top of the skirt. You can have the ends of the casing meet in the middle, or sew them together and use grommets, or button holes for your drawstring openings. Hope this helps!~*
http://www.angelfire.com/stars2/SunshinesCreations/clothingdemo.html there's a simple drawstring on the link. visuals too.