Being a good tourist means being respectful of others, their culture and their environment, along with following the rules of that country.
Be considerate: Don't disturb other travelers or locals with loud noises or over-the-top behaviors. Use your "inside" voice, please. Be mindful of the environment:  Leave nothing behind that says that you were there, and try to have as little impact on your surroundings or artifacts as possible. Don't be a litterbug: Pickup and carry out your trash! Follow the hotel rules: Check in and out at reasonable times, and read the local hotel regulations, including quiet hours and fire safety protocols.  Be respectful of the wildlife: Don't feed the wildlife unless allowed, and don't pet them unless your guide says you can. Be mindful of the locals: This is their home. Watch where you roam! See that your fun does not get in the way of others' properties or livelihoods.