This off-duty combination of a navy knit cardigan and khaki chinos is perfect if you want to go about your day with confidence in your look. With shoes, go for something on the smarter end of the spectrum and round off your getup with a pair of black leather derby shoes. As you're progressing through your late 20s, you probably want to start dressing like a grown man. In this case, combinations like this are a fail-safe option.