If you have a waterbed, lower the heater temperature by 10 degrees. Stop the newspaper. Many papers will donate your unused copies to local schools and other worthy institutions. If taking a plane, train or bus Ask your travel agent or transportation representative to issue paperless tickets. These electronic versions waste less paper and can actually speed you through lines, since you won't have to purchase tickets at the airport.
Airlines are notorious for stuffing everything in paper jackets.
When you get to the terminal or station at the other end, try using the hotel bus or van rather than renting a car. During your stay, relax and enjoy the scenery by leaving the driving to others or by taking public transportation. Even if you take a taxi, you'll keep an extra rental car off the road. At the hotel Have towels and linens changed only every other day. Even then, make sure that towels and wash cloths which haven't been used aren't replaced.