TUESDAY TIP! Silk screening with the sun! Using a sturdy piece of cardboard, followed by a piece of black fabric to reduce reflection, a prepared wood screen (bottom side up) with dry emulsion, the transparencies (face down), and finally a piece of glass to hold your image in place against the screen, you are ready to expose your image. Once you see it darken considerably it has been completely exposed....it should only take 2-3 minutes depending on how strong the sun is. If it is overcast it may take a few more minutes!