For a look that's classy and absolutely GQ-worthy, marry a navy plaid blazer with brown dress pants. Want to dial it down when it comes to footwear? Add a pair of white canvas low top sneakers to this look for the day. So as you can see, it's very easy to look sharp and stay cozy come chillier weather, all thanks to getups like this. Definitely a great choice if we're talking style tips for 30-year-old gentlemen.