High End: Use tach, lean to max rpm mixture setting and back off (richen) about 400 rpm shy of max lean

Low End: Adjust to obtain low idle with smooth transition to full throttle. I prefer to keep my idle slightly lean so it doesn't load up at extended idles.

Pinch test not reliable for 4 strokes and is best used with 2 strokes. If you can hear a significant different in engine speeds when you do the pinch test on a 4 stroke, you are too rich to begin with. A 400 rpm rich setting is barely, it at all, noticeable with a pinch test on a 4 stroke.