Before there was a SGP dots stencil, I used a perforated metal tray meant for grilling to get these lines of circles. I love the random raggedy edge of the burned cardboard. It's a tricky thing to do - wave a lit match along the side and see what happens. Be standing over a sink. Seriously. Sometimes the flame shoots up through the corrugated groove and you don't know where it will surface. Do this BEFORE the spray paint or you might be in peril.
