This combo of a navy blazer and navy jeans couldn't possibly come across other than outrageously stylish and effortlessly sophisticated. Send this ensemble a more casual path with white and black leather low top sneakers. So as you can see, it's super easy to look amazing and stay cozy when chillier weather comes, thanks to this look. You can take inspiration from outfits like this if you're in your mid-20s and you want to take a more adult approach to your personal style.