Apart from the will to dress down I would say that the pocket square is a great opportunity.
Youngsters today do not know how to use it and when they use it they have some multicolor thing in silk (which is totally unnatural as a handcachief).
I instead take the advantage of as often as I can have a pocket square in my jacket. Like I try to use suspenders instead of a belt
My advice (when not wanting to dress down):
* Use pocket square as often as you can. It is a part of your jacket as much as your buttons
* Dont make a big fuzz out of it. Just have a white cotton pocket square sticking up. Do not make a flower out of it, just keep it straight (1960-fashion).
And Mr Bond would use a pocket square.