I'm no expert but I would think if you made a long tube sleeve out of cotton fabric (something flexible) and slipped it over the cord it would do just fine. You might want to post your question in the Sewing Forum for a more better answer from those who sew more than I do.

Sal

Long tubes of fabric will work, but eventually the ruching will slip towards the floor. I would sew the long seam and then on the very edge, zigzag down it over a piece of cord or dental floss, something strong. Then you could pull and gather it to the required length, tie it off and take a little stitch here and there to lock it in place. Then the ruching will not slip. I've also seen them open on the side with velcro so slipping the cord in is super easy. I wouldn't bother with that though, it makes them too thick.

Thanks Flamey & Sal...it all makes sense now. I'll be using a baby pink or lavender chiffon type material. Your advise is much appreciated!