Start Composting
You won't find any bags of store-bought, chemically tainted topsoil at Nell Newman's cottage home in Santa Cruz, California. The president of Newman's Own Organics (that's her next to "Pa" Newman on the label of Ginger-O's cookies) saves nearly every kitchen leftover for her compost, including coffee grinds, eggshells, and even paper bags. Not only does composting cut down on trash, explains Newman, 48, it "encourages you to grow more, and that's always beneficial to the environment. "If you don't have a garden, use your mixture for container plants. "You can grow all kinds of healthy things in pots," Newman insists. This readily available source for natural soil doesn't cost a dime. To learn how, visit epa.gov/compost.

Start Gardening
From the production of petroleum-based fertilizers to the cross-country distribution of seasonal fruits and vegetables, the modern food system accounts for 10 percent of U.S. energy consumption. And yet as Michael Pollan, 52, points out, "We have at least 30 million acres of front lawn sitting around doing nothing for anybody." The best-selling author of "The Omnivore's Dilemma: A Natural History of Four Meals" suggests converting this abundant, idle land into a personal produce section. "If you take a 6- by 6-foot piece of your lawn and turn it into a garden, you'll be amazed at how much food you can get out of it." You'll not only save money; you'll be eating vegetables at the peak of their nutritional value.

Spend More Time Outdoors
Environmental stewardship is grounded in love, rather than anger, says John Passacantando, 45, executive director of Greenpeace USA and nature's ultimate ambassador. "If you find yourself spending less time outdoors, go back quietly and listen," he says. "What you hear will make you act." Choose an activity, such as hiking or gardening, or revisit your favorite outdoor spot. Passacantando favors the Potomac River in Washington, D.C., which he frequently visits on his way to work at night to view the amazing sunsets; he also goes to the river on his days off to kayak with his wife and two daughters. Once you find the place that motivates you, spend time there regularly. Let it remind you of what's at stake.

Take the Bus (or Train)
Adam Lowry, 32, is a chemical engineer who has helped the environment by creating Method Home, a maker of chic, nontoxic household cleaners. But he also helps out with daily "ecoadventures" -- another name for taking the bus, train, or subway. By doing likewise you help minimize your impact on the planet. Of course, even Lowry, Method's "chief greenskeeper," sometimes drives, and to offset the consequent emissions he pays for clean energy projects through TerraPass (terrapass.com). "It's a great near-term solution," he says, "but it's guilt management." To create lasting change, Lowry suggests getting involved with urban forestry projects, which use strategic tree planting to help provide climate control, prevent soil erosion, improve air quality, increase property values, and elevate the quality of life (communitytrees.org).

Think Big Picture
"When millions upon millions unplug charging devices, recycle all they can, and shop locally, the benefits add up," says Robert Redford, 69, actor, director, and founder of the Sundance Institute. He suggests joining an environmental organization such as the Natural Resources Defense Council (nrdc.org) or the League of Conservation Voters (lcv.org). By uniting people behind campaigns for clean energy, wildlife conservation, and toxic-waste cleanup, these groups hold critical sway over national policy. For Redford, thinking big isn't just about numbers, however; it shapes his personal philosophy. "It's always important to look at the big picture -- the global picture -- and see how it relates to your life," he says. "But it's more important to look at how it relates to the lives of generations to come."