Dressing well doesn’t always mean dressing up, and this is especially true for younger guys. If you’re still in high school or your early years of college, the idea of wearing a suit or even jacket most days is a bit beyond the mark. By all means, if you’re comfortable with it you should do it, but it’s not a requirement for the young guy.
The biggest thing a young man can take advantage of is fit. Most guys your age either go too skinny like the emo hipsters or too baggy like the skaters and thug wannabes. Most everyone else is just sloppy in the cargo shorts and graphic T shirt.
This kid is an excellent example. The lighter jeans fit but the color makes them more casual and younger. His shirt would appear to be just a regular button up but it fits him great. See the seams where the sleeves meet up with the body? Those are sitting right on the edge of his shoulders and that’s exactly where you want them. Most men wear shirts that are too big in the shoulders and it makes them look scrawny in comparison. He makes it look younger by having the majority of the buttons undone and keeping it untucked (this looks good because the shirt tails are short and meant to be left untucked. Don’t do this with a dress shirt).
He’s also wearing a bunch of bracelets and a big ring. Younger men can get away with following GQ trends a lot better than guys who have already finished college. Take advantage of the fact that last year and this year it’s huge to load up your arms with bracelets. The young women will look at everything else and see that you’re stylish. They’ll look at the one or two trendy things and see that you’re current. It’s a great cocktail for a young dresser.