This casual combo of a grey crew-neck sweater and charcoal skinny jeans is perfect when you want to feel confident in your ensemble. The whole ensemble comes together when you complete your outfit with grey suede low top sneakers. So so as you can see, it's a stylish, not to mention season-appropriate, ensemble to keep in your transeasonal rotation. When it comes to casual outfit ideas for 30-year-old gentlemen, this combo is perfect.