Why not rock a brown sweatshirt with charcoal chinos? These two items are very practical and look cool paired together. Feeling venturesome today? Switch things up with burgundy leather brogues. More elegant getups like this work handsome on 30-year-olds.
Consider pairing a brown sweatshirt with charcoal chinos for a simple menswear style that's also pieced together nicely. If you want to break out of the mold a little, introduce black suede chelsea boots to the equation. As a 30-something Millennial man, you probably want to start dressing like a grown-up. In this case, inspiration like this is very useful.