For an effortlessly smart menswear style, pair a blazer with red chinos — these pieces work really cool together. Complement your look with a pair of black leather double monks to switch things up. When temps are dipping and autumn is in the air, you'll love this ensemble as your uniform for summer-to-fall weather. As you're heading into your 30s, you probably want to start dressing like a grown-up. If that's the case, combinations like this are a foolproof option.