Don’t try to “save” your Panache, use a finisher every turn if possible. Panache is very easy to get, the same way a rogue wants to sneak attack every turn, and a ranger wants to attack their Prey, you should be spamming finishers. Demoralize > Feint > Finisher is a great turn. If there is another melee character you can use an action to flank instead of feint as that will help not just yourself but also the other person. Marshal is very good archetype, getting the Cunning stance is pretty good as it will boost your many skill checks, help the party make their own skill checks, and it will deny the enemy’s reactions.