A navy biker jacket and tan sweatpants are a nice pairing worth having in your day-to-day wardrobe. Athletic shoes are guaranteed to add an element of stylish nonchalance to this outfit. If it's one of those gloomy autumn afternoons, what better to spice it up than a dapper ensemble like this one? Those who are curious how to rock modern casual style as you get into your 30s, this combo should answer your question.