Who presided over the lottery before the balloon volleyball match?

The referee presided over the draw.

Pre-competition preparation:

The first referee presides over the lottery, and first chooses the right to serve and the ball area.

Second, the start process and stop of the game:

The first referee will stand at the end line of his own field after blowing the whistle, and stand in the original position when blowing the whistle again (the position table filled out before the game).