What GUI are you referring to?  I was just talking about the web interface.  I wasn't aware there even were other ways to fork.  Or maybe you were referring to the clone, which I guess can be done via the command line or with a GUI tool in addition to simply doing it from the web site?  I could add "or use git clone from your local machine" or something like that.  I like mentioning some amount of implementation detail so people can correlate what they read here with what they might read in a git tutorial.