You will need a physical image to begin working on your screen print. In my case that means a computer print of my Photoshop file. I am only using my digital print out as an image to trace so it is not important that it is high quality. Of course you do not have to start with a digital print out. A drawing, a photocopy, or a high contrast photograph will do the trick as well. The important thing to keep in mind is that your image should be easy to trace and divide into positive and negative space.