Step ONE
Reduce.
-don't buy and throw away as much or don't get things with lots of packaging.
Reuse.
-give items (packaging material, toys, etc) a second life and you can refill plastic bottles with tap or filtered water
Recycle.
-you know, recycle plastic, paper and tin etc
Renew.
-use renewable energy sources such as bio fuel, geothermal, hydro-electric, wind solar, etc
Step TWO
Replace those obsolete incandescent light bulbs with compact fluorescent bulbs. These may cost a little bit more, but save you up to 40% on your energy bill.
Step THREE
Don't leave your computer in "Standby" or "Sleep" all night. That uses sooooooooooo much energy. It is better for the plant plus it is cheaper for your electricity bill.
Step FOUR
Plant as many trees as possible. Trees help keep our air clean by taking CO2 out of the air and replacing it with oxygen.
Step FIVE
DO NOT run the water to long. Helps both you and the world. Don't run the water while you brush your teeth, it is simple easy and it can still make a difference even if it is a small one. The water bill can be reduced by fixing drips. If you get an energy star washer it can save water, electricity and your time.
Step SIX
You could take out the gas heating system & get a wood stove. Natural gas will run out.