Want to infuse your wardrobe with some fashion-forward cool? Pair a blue harrington jacket with a navy polo. White and red athletic shoes are the simplest way to give a dose of stylish casualness to your ensemble. When it's one of those bleak autumn days, sometimes only a killer ensemble like this one can get you to face the outside world. Those wondering how to wear modern casual outfits as you get into your 30s, this outfit should answer your question.