This combo of a navy chambray long sleeve shirt and a white crew-neck t-shirt is hard proof that a pared down casual ensemble can still look really interesting. Feel uninspired with this ensemble? Invite a pair of brown leather casual boots to shake things up. This is a goofproof option for a kick-ass outfit that will take you from winter to spring. When it comes to casual style tips for 30-something Millennial gentlemen, this combo is perfect.