How to improve fuel efficiency in my Vauxhall Corsa?

I recently purchased a Vauxhall Corsa and have noticed that it is not very fuel efficient. Is there anything I can do to improve its fuel efficiency? I would appreciate any advice.

Regularly check your tire pressure and make sure it's at the recommended level. Under-inflated tires can greatly decrease fuel efficiency.

Avoid unnecessary idling and aggressive driving. Both of these can significantly decrease your fuel efficiency.

Consider investing in a fuel additive or cleaning your fuel injectors. This can help remove any build-up and improve your car's performance.

Make sure your air filter is clean and replace it if necessary. A dirty air filter can decrease fuel efficiency.