The serve can be made by either the slammer or the setter. Hitting the 2x4 counts as a fault.
Double faults result in a point for the other team.
Serve stays with the serving team. A team's cups must be touching for play to be legal. A time-out can be called between points by separating your cup from your teammates. If your cups are touching, it's an indication that you are ready to receive serve, even if you aren't actually ready. Other House Rules may apply at the discretion of the host.