This document provides steps to create a Chrome extension that allows users to validate HTML pages with one click. It involves creating a manifest file, adding an icon, deploying the extension to Chrome, and adding popup.html and popup.js files. The popup.js uses the Chrome tabs API to get the current tab's URL and open it in the W3C validator when the user clicks the extension's button. The document also provides tips for debugging, packaging, and publishing the extension in the Chrome Web Store.