This pairing of a navy denim jacket and beige jeans is super easy to do and so comfortable to rock a version of as well! Kick up this outfit by finishing off with a pair of dark brown snow boots. In winter, when warmth is top priority, it can be easy to surrender to a less-than-stylish getup. However, this getup is a shining example that you can actually stay toasty and remain stylish in winter. And if we're talking casual outfit ideas for 30-year-old guys, this outfit is perfect.