If you're using two fingers, don't move them vertically in and out, instead make a curve facing up as if you're signalling someone to "come here".
Then increase the speed of the signalling to 5 come here per seconds.
Nimekanyanga weight hapa town kibahati mbaya, bro alikuwa anataka nilipe 20 na mimi namshow ata sijaona kilo zangu juu nilikuwa katika haraka zangu na si eti kitu ilikuwa kwa hesabu zangu, sasa alikuwa ana insist nirudie kupimwa na anifanyie na 10 bob๐, kama sio kanjo kutokea na kukimbiza hawkers vita ilikuwa itokee pale