For more casual settings, you can go a bit wild and experiment with funnier patterns and colors. Just remember to balance the tie with your suit and shirt. A pocket square used to be for business ...

Make sure your suit is mat, and free of business-like patterns such as pinstripes. Instead, opt for something a little more casual than you might be used to, such as this one from J.Crew.

Yesterday, for example, he rolled up to a TimesTalks discussion wearing an Etro suit and shirt that just about perfectly demonstrate how to mix patterns when you’re wearing formal clothes.