Steps to add external CSS to HTML. css by Naughty Nightingale on Feb 23 2020 Donate . In the folder save an HTML and CSS file. This modified text is an extract of the original Stack Overflow Documentation created by following contributors and released under CC … One of the main ways of adding CSS to your HTML document is with an external .css document. Internal CSS defines a unique style for a single HTML page inside the head section, inside the