When is a pocket square appropriate? What color should I wear? What kind of fold should I use?
There has been some debate about whether a pocket square is appropriate for all occasions. Although there is no easy answer, I believe the pocket square can be adapted to any situation.
A commonly cited concern is that a pocket square at the workplace will give unwanted attention and label you as an eccentric. I agree that if you are wearing a rainbow colored square that is bursting from you breast pocket, you may attract some odd glances. the solution is simple: a reserved white linen square, in a TV fold will never draw a negative response. It is a neat fold that will only be noticed by those looking for such detail. The key is judging your audience, and understanding norms.
When in social situations I am in the school of thought that the pocket square can be as pronounced as you wish. It is your opportunity to experiment with color and design. Try different folds, and find what you suits your style.
A word of caution: I would avoid matching tie and pocket square. The result is often amateur and a bit cheesy. Try complimentary colors that don't clash, but accentuate each other. For example, pink and green and gray and yellow are two of my staples.
For ideas on how to fold your square click here.