A black double breasted blazer and dark brown dress pants are absolute essentials if you're piecing together a dapper wardrobe that holds to the highest sartorial standards. Puzzled as to how to finish off? Introduce dark brown leather double monks to the equation for a more relaxed vibe. This look is a pretty wonderful pick, especially for autumn, when the temps are starting to drop. So as you can see this ensemble is something you can totally wear as a man in his thirties.