This is the blunt instrument approach to the topic...
Ten relatively painless things you can do for the environment:
10) Renew, recycle, re-use. Any time you re-use something instead of replacing it, you are doing a world of good. "He who dies with the most toys, wins" is selfish: his descendants lose.
9) Children are the single biggest drain you can produce on the environment. If you're planning your family, plan small and you will make a gentler footprint.
8) Use compact fluorescent bulbs instead of incandescents. Your power bills will drop, and they last forever, so it's a win-win situation. And if you balked at the price tag when they first came out, reconsider... they've dropped.
7) If you're female, choose a reusable menstrual cup or washable cloth pads instead of the corporate drain on your household economy that is the commercial feminine hygiene industry. (Your tender naughty bits will be much happier without the chafing paper and plastic, anyway.) Cloth diapers, too. If you wouldn't wear it on your butt all day, why would you do that to a tiny baby?
6) Use re-usable bags rather than "paper or plastic."
5) Choose organic fruits, vegetables, grains, and beans when available and not crazy expensive. They're available and in many cases (but not all) they are measurably more healthy for the consumer.
4) Cut down on emissions by carpooling, traveling less, and biking or walking more.
3) Use less toxic household and toiletry items. Choose ecologically sensitive, biodegradable, or organic options where available.
2) Vote with your wallet and your tummy. Try to get away from fast food. For bonus points, go vegetarian, or better yet, resist factory farming. Not only will you be reading ingredient lists on labels, and probably making choices that include less revolting chemical, petroleum-based, and animal ingredients, but you will be avoiding a major source of pollution. Advanced "carbon dieters" will become locavores, eating only products coming from local sources (I think we used to call it macrobiotics.)
1) Get politically active. Write letters, call your representatives, sign petitions. It takes only an hour or two a week to have a conscience you can feel proud of. Vote for candidates who understand that the future is worth planning for. Press for more sustainable industrial options (fully electric cars, more sustainable fuels, no lead shot, whatever ignites your personal passions).
(I am not anywhere close to perfect... just putting it out there.)