I always try to keep my pinky finger off the edge of the ruler to help stabilize it. Cut about 12 inches and then CAREFULLY move your hand up the ruler, leaving the rotary cutter blade IN the fabric and continue to cut. And Try to cut with the rotary blade at a 45 degree angle to the ruler, not tilted over and pushing against the ruler. ( you can have the handle at whatever angle is easiest for you to cut, just be sure the blade is straight.) Sometimes, we get to pushing so hard against the ruler ( it happened to me when my blade begins to get a little dull) that is moves our ruler.