The sign "NO" can use either a polite double motion or a more firm or definite
single motion. It is also directional in nature--meaning, if I hold my
hand off to my right and I point the palm toward myself while doing the sign,
it can mean "He told me no."
A firm, solid "no" as in a command. Uses one motion.
Another variation of no uses a double motion and a negative headshake.
Is done similar to the normal sign for "no" except that it starts off toward
the right and moves in toward your body.