The line between looking like a cowboy (or maybe a prisoner) and looking current is a blurry one. But the simplest way to think about head-to-toe denim is to consider a paint strip at the hardware store: practically all the same color, just in various, complimentary shades. Pair a chambray shirt or faded denim jacket with some dark jeans. Or dress up a denim shirt with a blue blazer and/or navy silk knit tie. Just remember to have a contrast between the weights and wear in the fabrics.