This pairing of a waistcoat and navy dress pants epitomizes rugged elegance. A pair of yellow leather loafers will introduce a more laid-back aesthetic to the getup. As you're heading into your 30s, you probably want to start dressing maturely. In this case, inspiration like this comes in useful.
Wear a waistcoat and navy dress pants if you're aiming for a sleek, smart look. White leather low top sneakers will bring an air of stylish casualness to an otherwise classic outfit. A great source of inspiration for 20-something gentlemen looking to move their style towards maturity.