To create a hyperlink, use your mouse to highlight the text you want to become your link. (Click at the beginning of the text, hold the left button down and drag to the end of the text, let go. Voila!! Highlight!) Just above your text editing box there's a bunch of buttons. Click on the one that looks like a little chain link . This will open up a new box to put your link info in.
Hand type in the URL of where it is that you want to link to. Of course, you can also copy and paste the URL into the box. If you'd like the link to open in a new window or the same one you can choose to do so in the Target drop down box. Be sure to give your link a title because search engines like links with titles!! When you're done, click insert. And you're linked!
To edit an existing link, highlight the text again, click the little (chain) link button again and make your changes.
To remove an existing link, highlight the linked text and click the little button with the breaking chain . This removes the link.
TIP: if you try to click the chain link button and nothing happens (or if it's very light or "grayed out") this means there is nothing to link - there's no text highlighted so it doesn't know what you want your link to be. So just make sure that your text is highlighted and try again.
Don't forget to scroll to the bottom of the page and hit submit to save your changes.
If your links aren't working like you want them to, try selecting extra text and clicking the breaking chain button to clear any existing links. After you've unlinked everything, save the page. Verify there are no hyperlinks on the active page and then edit the page again and try creating the hyperlink again as described above.