How To: Make Picture Frame Silk Screens

We seemed to have missed the high school art class where most people learned how to silkscreen, so while we've heard lots of times how easy the process is, we've remained a bit mystified...But after watching Michelle SaintOnge's demonstration on Martha today, we might finally be up to the challenge. Her instructions include several pet-inspired templates to use, but of course making your own would be a bit more fun. Have you made a silkscreen print before? Any tips?
Image: t-dot-s-dot