Reach for a grey shawl cardigan and a white crew-neck t-shirt for both seriously stylish and easy-to-create outfit. Our favorite of a myriad of ways to finish this ensemble is a pair of dark brown leather desert boots. This combo is a good choice when it comes to a killer summer-to-fall outfit. If you want to project maturity and professionalism as a 20-year-old gentleman, a look like this is a good option.