To achieve a relaxed casual ensemble with a modern finish, dress in a white and black horizontal striped long sleeve t-shirt and dark green cargo pants. You can take a classic approach with footwear and complete your outfit with a pair of burgundy leather brogues. Casual combinations for gents in their thirties aren't actually that hard, as you see here.
White and Black Horizontal Striped Long Sleeve T-Shirt with Burgundy Leather Brogues Outfits In Their 30s
Dress in a white and black horizontal striped long sleeve t-shirt and green cargo pants for equally stylish and easy-to-style getup. Take this outfit in a dressier direction by slipping into burgundy leather brogues. Those who wonder how to wear modern off-duty outfits as you move into your 30s, this combo should answer your question.