What is the best way to increase fuel efficiency in a Ford Focus?

I recently purchased a Ford Focus and I've noticed that I am not getting the best gas mileage. Are there any specific tips or tricks to increase fuel efficiency in this car?

Consistent and careful driving can greatly improve your Ford Focus's fuel efficiency. Try to avoid sudden acceleration and braking, and maintain a steady speed on the highway.

Make sure to regularly check and replace your air filter and spark plugs. These can greatly affect your car's fuel efficiency. Additionally, consider using a fuel additive to clean your engine and improve gas mileage.

Try to avoid unnecessary weight in your car, as this can also affect fuel efficiency. Remove any excess items from your trunk or backseats.