A navy crew-neck sweater and a crew-neck t-shirt are among those game-changing menswear must-haves that can completely change your wardrobe. If you're hesitant about how to finish off, a pair of white canvas low top sneakers is a tested option. So as you can see, it's very easy to look on-trend and stay snug come colder days, all thanks to combinations like this. Wondering how to nail semi-casual style as you progress through your teens? This pairing is a good illustration.