For a look that's street-style-worthy and effortlessly classic, consider wearing a blazer and black chinos. Black oxford shoes will infuse an added touch of sophistication into an otherwise mostly casual ensemble. In the colder months, when warmth is key, it can be easy to settle for a less-than-stylish ensemble. However, this ensemble is a good illustration that you can actually stay warm and remain equally stylish in the colder months. This combo illustrates how gentlemen in their 30s slay in the style department.