A black long sleeve t-shirt and blue jeans are a great outfit formula to have in your wardrobe. Want to go easy on the shoe front? Introduce a pair of black and white athletic shoes to the equation for the day. So if it's a warm summertime afternoon and you want to look dapper without putting too much effort, this ensemble will do the job in no time flat. This combo should clear any doubts you had about dressing casually in your 30s.