How to improve the fuel efficiency of my Volkswagen Touareg?

I have been noticing that my Volkswagen Touareg's fuel efficiency is not as good as it used to be. What steps can I take to improve it?

Regularly check and replace the air filter to ensure proper air flow into the engine. This can greatly improve fuel efficiency.

Maintain the recommended tire pressure to reduce rolling resistance and improve fuel efficiency.

Try to avoid idling for extended periods of time. This wastes fuel and can negatively impact fuel efficiency.