Linen absorbs dyes and paints particularly well. When you want to paint your shade a solid color, apply a piece of tape 1/8 inch from the edge on the inside of the shade. You can suspend the shade using a bent wire; this will allow you to turn the shade as you spray so that your coat of paint is evenly applied. Spray thin, even coats for a better finish. It may take several coats to achieve the color you want. Allow the paint to dry before gluing on trims.
Lamp shades are easy to paint with stripes. Go fat or thin -- simply press tape firmly to the shade surface. Tape around your inside rims. Suspend your shade and spray. You can alternate colors or make them all the same. Allow the paint to dry completely before you peel your tape so that the liquid color doesn't seep under the tape too much. Hot-glue trim around the top and bottom and you have a custom shade.
Fit lace over the shade and tape it to the inside. You want the lace to be tight, so you may want to add a few stitches along the seam just to pull it tight. Tape around your inner edges and suspend and paint. This can create a very dramatic shade. To make your shade even more unique, paint the shade a solid color first, and then add the lace stencil and paint a contrasting color. This will make your finished shade two-toned.
Cut shapes and designs out of adhesive-backed plastic. Press the adhesive onto the linen shade until you have the design and pattern that you want. Tape off borders and edges and paint the shade. The plastic will act to keep paint away from the areas it covers. This is a good way to add larger patterns to a lamp shade. After the paint dries, peel the plastic off at the same time you peel the tape.