This casual combination of a navy long sleeve shirt and black jeans is simple, stylish and very easy to copy. Introduce black leather chelsea boots to the equation to completely switch up the outfit. During the winter season, when comfort is the priority, it can be easy to settle for a less-than-stylish look. This look, however, is a stark illustration that you can actually stay snug and remain equally stylish in the winter season. Ideal if you're in search of some seriously inspiring style for 20-year-old men.