A navy cable sweater and jeans are amazing menswear staples that will integrate perfectly within your casual fashion mix. A pair of white leather low top sneakers looks great here. Casual combinations for gents in their thirties aren't actually that hard, as you can see.
Go for a navy cable sweater and jeans for a daily getup that's full of style and personality. Brown leather casual boots will create a stylish contrast against the rest of the getup. This pairing illustrates how to keep succeeding in the casual style department as a gentleman in his 30s.
If it's comfort and functionality that you're looking for in an outfit, make a navy cable sweater and jeans your outfit choice. And if we're talking casual style for gents over 30, this ensemble is perfect.