Amplify’d from www.goenglish.com
When In Rome (Do As The Romans Do)
( a visitor should try to act as the people do who are from that place ... )
When in Rome, do as the Romans do means that when you are visiting a new place, you should try to do as the people do who are from the place.
People from different places have different ways of acting, so it is important to try to do things the way people do who are from the place that you are visiting.
See this Amp at http://amplify.com/u/dje4