This off-duty pairing of a multi colored print fleece zip sweater and black jeans is perfect when you need to feel confident in your getup. Get a little creative when it comes to footwear and dress up your ensemble with a pair of navy leather casual boots. As you can see, it's very easy to look on-trend and stay cozy when cooler weather arrives, thanks to this outfit. And if we're talking casual dressing ideas for men in their thirties, this getup suits almost anyone.