For coding?
I just search the web and standardize on something. Internally the team found a design doc on the net (Microsoft based I believe) and adopted and tweaked it to something we all agreed upon.
For example I did a quick search just now and found
http://www.dotnetspider.com/tutorials/B ... tices.aspx
Which has a good small set of guidelines. I use the same guidelines no matter the language I use now. But for example, it says that m_varName is an old style and that m_ is no longer valid as a general practice. But yet VB6 (and possibly other languages) don't allow vars to start with _ (to make _varName) so you have to put something so I still use m_varName in vb6