When executing facing movements while armed with a rifle, do not break vertical. But, what does that mean?
In Regulation Drill, drill that is based on the drill and ceremonies manual for each military service, without any added movements whatsoever, Drillers must execute the movements exactly as described.
The preparatory commands for facing movements are Right, Left and About. Do not lift the rifle off the marching surface on the preparatory command. Accomplish that only right after the command of execution, Face, while executing the first count of the movement (see the pictures, above).
When you move, the rifle must remain vertical, lift it just enough to clear the ground/deck and move it to directly next to the right foot on the second count of the movement.