Use less fuel:
Avoid unnecessary braking and acceleration.
Keep your tires properly inflated.
Remove extra weight from the car.
When doing errands, try to combine them to reduce your driving.
Avoid getting stuck in traffic.
Use less air conditioning.
Buy used ~ Buy Hybrid or electric vehicles
Walking ~ Biking;
Walk or bike within 2 miles of home
Walk or bike to public transit
Trains and Subways;
Less air pollution
Less emission per person because it is shared
Develops electric transport systems.
Less production embedded than individual cars
Flying contributes about 2% of the world's global carbon emissions plus the infrastructure embedded in the industry
Fly shorter distances
Fly economy class.