A white and black crew-neck t-shirt and yellow shorts are a modern casual pairing that every trendsetting gentleman should have in his casual sartorial arsenal. Puzzled as to how to finish this look? Wear a pair of loafers to elevate it. This here is hard proof that you actually can survive the sweltering heat, all while looking fresh and clean. When it comes to casual fashion tips for 20-year-old gents, this ensemble looks cool on most men.