If you are installing this as part of the class,n use CommandBox and go to the /ThisIsTheRootOfTheWebSite/your_folder and type install git://github.com/djcard/learncf.git.
If you are looking at this outside of the context of the class you can simply type install git://github.com/djcard/learncf.git in an empty folder, cd to /learncf, and then type server start to see the content.