This is an excerpt from Volleyball Fundamentals 2nd Edition PDF by Joel Dearing.
Once a team on defense anticipates during a rally that their opponents cannot attack their third contact, they simply need to call out “free ball” and move to the W formation. This example of moving from defense to preparing to play offense is called transition. Transition will be covered in more detail in chapter 12, including match situations when you also move from offense to defense.
To move from base defensive positions to create a W formation (figure 10.1a), the player already in zone 2 as a blocker can be designated as the setter and should take a position near net zone 6. Blockers in zones 3 and 4 turn and run straight back behind the attack line to prepare to attack, and now join their teammate in zone 1 to form a straight line, while teammates in zones 5 and 6 position themselves as shown in figure 10.1b to create the W. Five players are now in position to receive the free ball.