Nail off-duty in a long sleeve shirt and dark green chinos. Let your styling chops truly shine by complementing this ensemble with a pair of black suede desert boots. In the colder months, when warmth is key, it can be easy to settle for a less-than-stylish ensemble in the name of functionality. But this ensemble is a striking example that you totally can stay toasty and remain stylish in the colder months. And if we're talking casual dressing ideas for 30-something Millennial guys, this outfit looks great on almost any guy.