How to add clickable links in your clip description?

I'm trying to add clickable links to my other less popular tracks on my best selling tracks, but I constantly end up with links that have to be manually copied to the browser. Any of you guys know how to make links like this guy is having in his description under "other popular tracks"? The link is bellow:



http://www.pond5.com/stock-music/34598884/heroes-united-dramatic-uplifting-trailer.html?ref=ScoreStudio#1