You'll be surprised at how easy it is for any gentleman to put together this off-duty look. Just a white crew-neck sweater and charcoal chinos. Clueless about how to finish off? Add a pair of low top sneakers to the equation to mix things up. As a 30-year-old gent, you probably want to start dressing like a grown-up. If that's the case, getups like this are a solid bet.