You may choose to change the default ads text. The default ones are:

To change these ads, make your pointer click on the paint bucket icon in the Admin Panel and click Theme settings.

Click on Ads header + to expand this section.

Here you can change each ad to whatver text you like
If you want to include a link in the ad, you should do this with an HTML tag, like this:
<a href="websiteurl_here">link text</a>
So, for example, a tag like this:
<a href="http://google.com">Google</a>
would result in the link: Google
When you are finished, click the Save changes button.
So, for example, a tag like this:
<a href="http://google.com">Google</a>
would result in the link: Google
When you are finished, click the Save changes button.