This is another cutting method for right-handers using two rulers. I placed my fabric so that the selvage edges are together at the top with the right sides outside. I'm going to fold my fabric a second time bringing the folded edge up so I have four layers of fabric here. But my edge isn't even and I need to square it up. For the two-ruler method, I use a large square ruler and I use any horizontal line along the bottom edge where I folded it, squaring my fabric to that line. I'm not concerned with the lines on the mat -- just the lines I'm looking at on my ruler. So I want to get this within about an inch of the edge, but you can see things don't line up here yet. So with my large square ruler lined up on that horizontal line, I'm going to take another ruler and abut the two together so there's no space here. I'm going to place my left hand on the small ruler, pressing down on my fingertips. I might even use my little finger along the outside edge to stabilize it. You don't want to place your hands flat because you don't have control things and sort of slip around. So I want to abut those rulers, have my fingertip pressure on it, and my little finger holding it, and I'm going to slide away the large ruler. I'm going to expose the blade on my rotary cutter (you always wanted to keep it covered until you're using it). I'm going to press down and away from myself to square up the fabric edge. Simply remove that piece. I have a nice square edge. Again I'm not concerned with the lines on the mat, only the lines on my ruler and I am ready to begin cutting. So I use the line on my ruler here. For the desired width that I want to cut. Put my pressure with my fingertips on and I'm ready to cut again. With the two-ruler method, once you make that first cut you don't have to move to the opposite side of your cutting surface. You're ready to go. And your strips will come out straight every time. That's the two-ruler method.