A blue denim shirt and cargo pants are the kind of off-duty must-haves that you can wear for years to come. If you want to easily amp up this outfit with shoes, complement this outfit with burgundy leather brogues. As the weather starts to cool down, you'll find that a look like this is ideal for fall. Casual outfits for stylish 30-year-old gents aren't actually that hard, as you can see here.