Just pop the Chrome add-on into your browser and get shopping. If you're on an associated retailer's site, the "Try For Free" button will show up automatically and you'll be able to order through the service. They'll send you your gear, along with a pre-paid return shipping label. If the clothes don't fit, just use the label and ship it back within 10 days for free. Best of all, you're only charged the online retail price—no extra fee—if you don't return the clothes, so this is a no-risk, all-reward setup.