To leave comments and get a dofollow link you'll need to leave the link in the body of the comment like this.
How about some free kung fu lessons
or you can simply add the url like this
http://www.freeonlinekungfu.com if you want just a url link.
adding links right in the text is much better for SEO anyway.
Links to specified hosts will have a rel="nofollow" added to them.
More information about formatting options
Calaveras County Martial Arts
Follow me on Twitter