Here are some ideas that can help you reduce your CF, and as an added bonus these measures are likely to save you money too !

Lifestyle
Get into the habit of walking a short distance instead of driving around waiting for a parking space
Buy quality products that will last many years instead of buying cheap inferior products (Tools, DVD Player, etc)
Take your own bags to the supermarket
Recycle as much as you can
Educate those around you in the ways of green thinking
Buy locally grown vegetables instead of foreign air flown vegetables
Complain if restaurants, cinemas, offices or shops are too cold
 
Electrical
Switch off all items when not in use (e.g. phone chargers).
Switch off all items before you go to bed
When buying electrical goods (e.g. air-con) buy energy efficient ones
When your light bulbs break, replace with energy saving bulbs
Turn down your water heater to reasonable temperature, set air-con temperature to 24 degrees
Don't leave windows open if you use your air-con
 
Laundry / Kitchen
Press "half load" button on your washing machine if the washing machine is not full.
Don't wash clothes if they are still clean
Boil only the amount of water you need and not a full kettle
Re-use empty containers and bottles
 
Bedroom / Bathroom
Install ceiling fan instead of using air-con
Take shower instead if bath
Don't spend more than 5mins in the shower
Let hair dry naturally instead of using hair dryer
Don't flush toilet un-necessarily
 
Car
Slow down. You will save a lot of fuel. Most engines are at maximum efficiency between 65-80 km/h. Driving over 100 is worst
Remove un-needed junk out of the car, this will make it lighter and more efficient.
Keep tyre pressure at correct pressure
Keep car properly serviced to improve engine efficiency
Drive a smaller more economical car
 
Outside
Plant trees around your house.  This will provide shade.
Collect rain water and use this to water your plants
Compost food waste
Do not do "open burning" of leaves and other debris
 
Advanced
Install a solar hot water heater
Install solar panels for electricity generation
Cycle instead of using car (if safe route is possible)
Buy a hybrid car (although it remains to be seen if these really are environmentally friendly)
Try to car pool to work if you live near to your colleague