This elegant combination of a dark green plaid blazer and a light blue dress shirt is a common choice among the sartorially superior gentlemen. A good pair of dark brown leather loafers is the most effective way to punch up your look. Entirely appropriate for hot weather, you can sport this look throughout the season. As you get into your 30s, you want to start dressing like a grown-up. In this case, getups like this are ideal as inspiration.