If the situation permits casual urban dressing, you can opt for a grey hoodie and cargo pants. If you want to instantly ramp up your ensemble with shoes, why not complement your look with a pair of dark brown loafers? This ensemble should erase any doubts you had about dressing casually as a 30-year-old.
This pairing of a white and black horizontal striped long sleeve t-shirt and cargo pants is on the off-duty side yet it's also seriously stylish and incredibly dapper. When it comes to shoes, go for something on the smarter end of the spectrum and round off this ensemble with a pair of dark brown loafers. This combo proves that passing the big 3-0 is no reason to stop dressing casually.