For an ensemble that's truly GQ-worthy, team a grey horizontal striped crew-neck t-shirt with a navy check suit. You could perhaps get a bit experimental in the footwear department and add a pair of black leather chelsea boots to the equation. So if it's a warm weather day and you want to look seriously stylish without putting too much effort, this outfit will do the job in no time flat. And if we're talking fashion tips for 30-year-old gentlemen, this look is perfect.