A timeless tip but a good one: Always bring reusable bags to the grocery store. According to EarthShare, if you grocery shop once a week, in five years' time, you'll have prevented anywhere from 250 to 1,000 grocery bags from getting into the landfills. But why only bring reusable bags to the grocery store? Use them at the hardware store, when you shop for clothes or at any store where you can opt out of using a bag. And if you forget, ask if the store can put your items in a cardboard box -- there are usually lots in the back -- and put it in the recycling bin as soon as you get home.