What are the requirements of balloon volleyball rules for serving?

(-) The serve must be clearly thrown from the hand, and then hit the ball with one hand or arm, so that the ball directly crosses the net from two marker posts. If the ball touches the net, it is judged as a mistake. (2) In the first game and the deciding game, the player 1 of the team with the right to serve will serve first. The second game is served by the team that serves first at the end of the previous game. (3) When the server wins a ball or the receiver gets the right to serve, the players must rotate one position clockwise, and the players who rotate to the position of 1 serve. If the serve is not rotated in the order of serving, it is a rotation mistake, which must be corrected immediately and the right to serve will be lost. (4) The server must serve in the terminal service area. He can move or take off freely, but he must not step on the line or go beyond the service area when hitting the ball, and he can land on the court after hitting the ball. (5) The server must serve within eight seconds after the first referee rings the bell. The ball was thrown by the server without hitting the ball, and the ball landed without touching the server and the server. The first referee should blow the whistle again and continue to serve. (6) The server shall not in any way prevent the opponent from observing the flight route of the server and the ball.