A few ideas to share –

• Consider eco-friendly tourism and accommodations.  There are a lot of adventures and resorts out there keeping the environment in mind as a priority.  Google eco friendly vacations, there are sites such as greenhotels.com, and ideas on eco-travel destinations
• Unplug all electrical items not in use – remember they still use electricity (vampire energy) when they are plugged in, even if they are not in use) – i.e TV’s, microwaves, chargers, lamps, clocks, etc.  Make sure your AC is off.
• Stop your mail and have it kept at post office (less mail for them to carry on the truck!)
• If you are booking flights – non-stops are the most fuel efficient as a great deal of fuel is used in take-off and landing
• Consider staying in one place longer and enjoy it more fully rather than touring numerous locations.
• While on vacation consider using public transportation or bike or walk… have fun getting to know the culture better through their local transit system or exploring it by foot.