Even easier than that, you can use the buttons at the top!
1. Press the "Link" button and paste in the URL. 2. Type what you want the hyperlink to say. 3. Press the "/Link" button, which will put the /url in bbcode brackets for you, and complete the link.
First, you go to the site (or page) you want to hyperlink. Go to the link and copy and paste that link (When you click the link button on the forums) the say want you want to say to make it be "Clickable". EX: