When you arrive home, take the time to reverse park into your garage/parking lot.

Do this while the engine is already up to temperature instead of spending time in the morning reversing and maneuvering the car out while the engine is cold and consuming more fuel.

It also helps if you're late to work and reduces the wear and tear of a cold gearbox shifting between reverse and forward.
by BenjaminWKI on February 08 2011
this tip works for 78% of voting Fuelly members.