How can I improve the fuel efficiency of my BMW M9?

I recently purchased a BMW M9 and have been frustrated with its fuel efficiency. Are there any modifications or driving techniques that can improve the car's fuel economy? Thank you in advance for your advice.

First, make sure your tires are properly inflated. Underinflated tires can significantly decrease fuel efficiency. Also, try to avoid aggressive driving and excessive idling. These habits can waste a lot of gas. Lastly, consider upgrading to a cold air intake or high-flow air filter for your car, as these can improve the engine's air flow and potentially increase fuel economy.