Eliminate plastic bottles by installing onboard refill stations for reusable water bottles, encouraging passengers to bring their own bottles, and reducing plastic waste.

Fill up empty seats by selling affordable return trips to unknown/secret destinations. Pick the destinations among those that have low occupancy close to departure time.

If possible, adjust aircraft speed to reduse fuel consumtion

Award additional EuroBonus bonus and/or level points when renting an electric vehicle through a car rental partner such as Hertz, Avis or Sixt.

Implement the potential to offset carbon footprint by CDR technologies like enhanced rock weathering;

International ban on private jets. Everyone can fly commercial. With option like business and first class this should be achievable if all nations want to reduce emission