Originally posted by BigJim: find your canine tooth through your upper lip. When you put a little pressure there, you can find it easily without opening your mouth. It is also on your upper jaw so it will always be a consistent anchor pt unlike the corner of your mouth. the corner of your mouth is soft and flexible and some days you may drag into it deeper than others. Also hold your head straight up and down. If you have a tendency to lean into the string it can get painful.BIgJim