Pick garbage up off the ground even if you didn't leave it there. Reduce the amount of toxic chemicals entering waterways, drinking water supplies, fisheries and other foods by not dumping chemicals down the drain. Reduce the amount of water you use and use it wisely. Take shorter showers. Don't leave the tap running when you clean your teeth or wash dishes.
Fresh water is a far more precious commodity than is generally realized.
Rinse out and reuse plastic bags, plastic containers and glass jars. Reuse old bags to do your supermarket shopping. Buy and use recycled and non-bleached paper. Be An Amazon Activist and Planet Neighborhood on PBS Online.