This pairing of a grey hoodie and black and white vertical striped sweatpants is a safe and very fashionable bet. And if you need to effortlessly perk up this look with one single piece, why not add black suede low top sneakers to the mix? This one is a viable option if you're putting together a knockout outfit for unpredictable fall weather. Guys who wonder how to sport cool casual style as you step into your 30s, you have your answer.