Such essentials as a white crew-neck t-shirt and black dress pants are an easy way to infuse some class into your casual styling rotation. For a more relaxed take, why not complete your getup with white athletic shoes? In the winter months, when functionality is key, it can be easy to surrender to a less-than-stylish ensemble in the name of practicality. However, this ensemble is a bright example that you can actually stay comfy and remain stylish in the winter months. As a guy in his thirties, you want to start dressing like an adult. That's when combos like this come in handy.