Some GR Tennis Courtesy Guidelines:
Please get the attention of the person on the other side of the net before you ‘toss’ the ball(s). Then toss them in a manner so that they can ‘catch’ it. Nobody likes to chase the balls.
Announce the score before you serve so that all can hear.
When you want a water break, please announce “Water Break” in order that other players on your court may take the ‘same’ break.
If the third ball is in a safe zone and the server is ready to serve; let the third ball be.