Team a dark purple sweater vest with mint chinos to put together a casually sleek and well-executed outfit. To add a little classiness to your outfit, opt for a pair of brown suede derby shoes. As you can see here, this ensemble is a really smart idea, especially for in-between weather, when the temperature is dipping. As a guy in his 30s, you want to start dressing like an adult. That's when combinations like this are a safe option.