I also have shakey hands and I've limited my coffee intake to just 1 cup a day to help alleviate some of the shakes. I also have trouble cutting even when using a ruler but not as bad as when I'm running strips thru the machine. I use a 1/4" foot with a flange and even then I can't seem to keep it up against the flange. I've had to go back where I really messed up and stitch that area again from time to time. So you're not a lone by far. This is also one reason why I have robotics on my quilt machine as I could stitch a straight line using a ruler let alone free hand.