1. Measure carefully. Measure the top edge of the lamp and the bottom edge, all the way around. You also need to measure the height and the radius (from the center out) at the top and the bottom. 2. When you draw your pattern, you want to create a sheet of constant width - but it won't just be cylinder. The easiest way to do this is to take a sheet of newspaper and wrap it around the lamp and tape it in place. Then cut carefully as near the edges as you can, so you get a piece of newspaper that is the same size as the lampshade you want. Now untape and lay it flat - smooth out any edges and cut them so they are neat. MAKE SURE YOU HAVE 1/2 to 1 INCH OF OVERLAP on the edges of the paper (more will look ugly). 3. If you are going to paint or color the paper or lamp surface do it before cutting. You can do this with stickers from an art store, or with stenciles, or cut out pieces from a magazine or other book (look at decoupage on the crafts page). You can even draw by yourself freehand if you like or trace piectures. To paint, use a sponge or paintbrush or toothbrush to dab on paint and create textures. Let the paper dry completely before you cut it. Press it flat under heavy books to keep from wrinkling. In metal, you can cut out shapes as well, or slits to let the light through. A transparent or translucent paper will work beautifully, and holes and cut-outs can be lined with colored plastic for a stained-glass effect.
4. With pencil (NOT PEN!) trace the newspaper pattern onto the paper you are going to use. Use a point to mark metal. Cut it out and place over the lamp - pull tight and paper clip in place - mark on the inside where you need to glue. You can glue it together then affix to the lamp with staples or hot glue. Metal can be secured with brads or even just tacks that you can let show or cover. You can even add lace or some other material (like a fringe) with a hot glue gun as a border or edging.
5. Voila! A lampshade suitable for your home.