Each team is allowed three contacts with the ball to get it over the net.  Points are scored only by the serving team except in the deciding set, and the points are gained if the opposing side fails to return the ball to the the net. or a winning shot is played where by the ball lands in the opponents' court.  In the deciding set the rally point system operates.

The serve is carried out by the back right-hand player.  Your team stops serving when the other team hits it back and you don't hit it back over.  That would be could a dead ball.  To serve you have to be out of the court.  If you step into the court while you are serving it goes to the other team.  That is called a foot fault.  You get one point for one serve if it lands on the other side.