You can reduce your carbon footprint if you change your driving habits either by taking the public transportation or carpooling, it drastically reduce CO2 emissions.
You can also drive under the speed limit, driving over the speed limit and excessive acceleration waste gas (reducing mileage by up to 33%), money, and result in an unnecessarily higher carbon footprint.
In your home, you can turn off the lights you’re not using and when you leave the room. Replace incandescent light bulbs with compact fluorescent or LED ones.
Insulate and seal your home: Reduce drafts and air leaks with caulk, insulation, and weather stripping.
Thermostat: Don’t set it too high or low. Install a programmable model to turn off the heat/air conditioning when you’re not home.
Food:
It has been estimated that 13% of U.S. greenhouse gas emissions result from the production and transport of food.
Buy local and eat a more diversified diet including less meat and dairy to reduce your carbon footprint resulting from the use of fossil fuel-based fertilizers, pesticides, and gas required to produce and transport of the food you eat.
Source:
http://cotap.org/reduce-carbon-footprint/