How do I perform a rollball?

The attacking player positions on the mark, faces the opponent's try line, makes a genuine attempt to stand parallel to the sidelines, places the ball on the ground between the feet in a controlled manner and then does one of:

• steps forward over the ball;
• rolls the ball back between the feet no more than one metre; or
• passes a foot over the ball.

Breaking that procedure is a change of possession to the defending team at the point of the infringement.

Other points:

• The rollball must be on the mark and without delay (penalty to the defending team). A voluntary rollball, done before a touch is made, is also a penalty.
• Another attacker, called the half, receives the ball without delay. The half may control the ball with a foot before picking it up, and stops being the half once the ball is passed on.
• The half may pass or run with the ball but cannot be touched while in possession. If they are, there is a change of possession.
• A rollball is taken seven metres in-field when a player in possession steps on or outside the sideline before a touch, or when a loose ball hits the sideline or ground outside the field.
• A tap cannot replace a rollball.
• Defenders must not interfere with the rollball or the half. The penalty is ten metres forward of the infringement.

Source: FIT Playing Rules 5th Edition, rules 10.7, 13.