PGSS sign for TAP1

TAP1 (to tap)
Hold 1st hand as SURFACE, and hold 2nd 1st finger hand but with its 1st finger bent, back upward and 1st finger pointing forward-inward, one hand's breadth above 1st palm; then move 2nd hand downwards till tip of its 1st finger touches 1st palm: return to original position and repeat action.