Don't try to pull an Extreme Green Makeover: Life Edition on yourself--start out small in order to ensure lasting success. "Going green doesn't have to be all or nothing," says Snow. "If you expect too much of yourself, you're going to fail. Pick one green thing and do that for a month or two, until it becomes a habit. Then add another thing, and so on. If you try to go green all at once than it's not sustainable and, most likely, not lasting."