Perhaps this is what you meant, but I'd strongly suggest any verbalization be
along with signalling. That way the players are learning the signals (wand we as referees don't get into bad habits about not signalling).
For
@Jay99 , I'd echo what
@one said about whistling--the more confident you sound/look, the more people will assume you know what you are doing. To that end, I'd even suggest practicing whistling--the simple twee, the hard
I don't like that! whistle, the peep-peep to get attention to tell someone where the throw in is. And along the same lines, silly though it may sound, go do signals in front of a mirror so you see what you look like--straight arms and confidence are your goals.