You should all ways keep moving a still fighter is a dead fighter.
Guards should not be assumed for long. Your opponent can tell what strikes you will use against him, and can tell what to counter your strikes with. Just as you start to assume a guard move rapidly to another guard and then attack. The Masters say to learn 4 guards Roof, Fool, Ox, and Plow. Wrath is thrown in because it is used frequently in Meyer. It is also said many times that Long point is the best guard to be used, but it is not initially mentioned in the explanation, but is referred to later in the text.
Guards to use in fighting
Offensive: Roof, Fool, Wrath.