Electricity
First, think about your home. If you're leaving lights on when you don't need them, turn them off. Switch off electrical appliances at the wall, don't leave them on standby.
Turn down the heat
There's a good chance that your central heating and hot water use a gas boiler, so whenever the boiler is on, it's burning gas and releasing more carbon dioxide into the atmosphere. Try turning your heating thermostat down to 20C. If you feel a bit chilly indoors in winter, try putting on a jumper first, don't just turn up the heat!
Keep out the cold
You can also think about eliminating draughts, fitting heat reflective panels behind radiators to make them more efficient and keeping doors and windows closed to keep the heat in and the cold out.
Switch to renewable energy
You could look at switching to a green energy supplier for your home's electricity and gas. We still use fossil fuels like gas to generate a lot of our electricity here in the UK. Click here for how.
So if you're going to change your energy supplier, look for a 100% renewable tariff. If you shop around, some green energy tariffs are now really competitive.
To take this a step further, you could think about installing renewable energy for your home. You can use solar heating panels to make hot water and photovoltaic panels to generate electricity. You could also consider greener heating alternatives like air- or ground source heat pumps, which use much less energy and emit less carbon dioxide than gas boilers.