An olive shirt jacket and beige cargo pants are essential in any modern man's well-balanced off-duty wardrobe. For something more on the sophisticated end to complement this outfit, complete this ensemble with a pair of dark brown leather casual boots. In the winter months, when functionality is imperative, it can be easy to surrender to a less-than-stylish outfit in the name of practicality. This outfit, however, is a bright example that you can actually stay toasty and remain stylish at the same time in the winter months. And if we're talking dressing ideas for 30-something guys, this ensemble is ideal.