Until early 2014, the guidelines were here: http://cf-pcmdi.llnl.gov/, but now there is a link to http://cfconventions.org/, and then a list of standard names, but the guidelines page that this points to does not (currently) exist.
I think it would be helpful here to have a link to the appropriate documentation, but also a summary of the guidelines (i.e., how to construct variable names that are consistent with the CF approach). In addition, any feedback on the standard_name field in my draft would be appreciated.