For a casual and cool outfit, consider teaming an olive shirt jacket with a black crew-neck t-shirt — these pieces fit pretty good together. If you need to immediately amp up this outfit with a pair of shoes, why not introduce a pair of dark brown leather chelsea boots to the mix? So if you're after an outfit that's on-trend but also feels entirely spring-friendly, look no further. All in all, a great insight into fashion for 20-year-old gents.