For an outfit that's super easy but can be smartened up or dressed down in a ton of different ways, consider wearing a shawl cardigan and a charcoal v-neck sweater. As a young guy, you want to start dressing like a grown-up. If that's the case, looks like this prove useful as a source of inspiration.
Such must-haves as a shawl cardigan and a charcoal v-neck sweater are an easy way to inject some masculine sophistication into your casual rotation. Balance out your outfit with a more casual kind of footwear, like this pair of dark brown leather work boots. A good example if you want to lose your boyish look and start dressing more maturely.