The pocket square is the canary in the menswear coal mine, announcing a man’s decision to view his clothes as an opportunity rather a necessity. Many writers have heralded the pocket square as the mark of a truly natty dresser - Bruce Boyer wrote that “a gentleman should wear a pocket square”; retired menswear doyen Will Boehlke used to say that most men should have half as many ties and twice as many pocket squares.
There are many ways to wear a pocket square, but only one rule – always complement; never match. As with tie knots, card tricks, and pick-up lines, you want to look good without seeming like you put in too much effort. Any hint of contrivance and the magic is gone. For pocket squares, that means looking like you grabbed something at random (n.b.: use caution in applying this logic to pick-up lines) and things just happened to work out perfectly.