Stance question

So what's the deal with the "stance" skills in my skill tree exactly? Because I'm going for a katana braver so I upgraded my tree with the basic stance and then on my sub class I went hunter and upgraded my fury stance but I don't know how to activate them in combat exactly.. or are they just automatically activated? Can someone help me out here?

Hunter, Fighter, Braver, and Bouncer each have two Stances. One set of these Stances are passive, ie. they are automatically activated as long as you put SP into them (Fury, Valiant, Basic, Elemental); the other set (Guard, Wise, Precision, Break) must be activated using their icon from your subpallette and they turn off the effects of their passive pair, for example, activating Guard Stance will deactivate Fury Stance.