This pairing of a navy long sleeve shirt and navy chinos is pulled together and yet it's functional enough and apt for anything. With shoes, take a more casual route with grey low top sneakers. And if we're talking style for 30-something Millennial men, this combination looks great on most gentlemen.
Such pieces as a navy long sleeve shirt and navy jeans are an easy way to infuse some cool into your current casual routine. If in doubt about the footwear, stick to grey low top sneakers. As a 30-something Millennial guy, you want to start dressing more maturely. That's when combinations like this are a life saver.