3. Buy environmentally friendly things. Buy recycled, buy local, buy "green". Not every "green" thing really is better for the environment (sometimes it's just a marketing gimmick), but if you're intelligent and careful, you can reduce your environmental impact by buying things that were made from re-used materials, or didn't have to be transported as far, or that are made with readily renewable resources like most plant fibers. Doing any of those things will tend to reduce the environmental impact of your purchases.