Google it and it should come up on the doityourself website. I also know that Jo Ann's has kits you can buy back by the lighting section. If you figure it out...let us know!!! I am interested in doing it too but I am not there yet with the decorating.
The JoAnn's kits are supper easy, they have a shade ready to go with a sticky adhesive and you get a pattern with it to help cut the fabric. It's in the back of they store, I did two! Supper easy, good luck!
Re: Covering a lampshade with fabric