This combo of a tan crew-neck t-shirt and navy jeans makes for the perfect base for a cool and casual look. And if you need to effortlessly dial down this look with a pair of shoes, why not introduce red and white athletic shoes to the equation? You're guaranteed to always look great even despite the summer heat if you have this ensemble as your go-to formula. Casual combos for guys in their 20s aren't actually that hard, as you see.