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Wearing a shirt casually is a go-big-or-go-home sort of proposition. If you're going to roll up your sleeves, don't quit prematurely. Roll past the elbow. It'll be a little bit naturally disheveled at that point. Let it be—don't try to be excessively tidy, nor intentionally sh*t it up J.Crew style.

Wearing an open collar calls for the same approach. It can't look like you just took your tie off; otherwise don't bother. Have the right kind of collar, ironing, starch and upper torso to make it look intentional. Pro tip: if full chest exposure isn't for you, or for your workplace, or for polite society in general, a double-breasted coat or a v-neck or cardigan layer will give you a higher button point for open-collar demarcation and containment.

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