That is actually pretty easy.

1. register domain at a registrar that supports email catch all (I use namecheap, not affiliated)

2. setup email catch all (https://imgur.com/a/PTlzv) with redirect to your "real" email

3. write email to [email protected] -> get's redirected to your "real" email

This has the big advantage that you can change your real email account (I switched away from GMail two years ago) quite easily, you can track who leaks your address and filter more easily. But be prepared to leave some people stunned, I registered at my electricity provider with [email protected] or at my hairdresser with [email protected]

Thanks! (Belated)

In my case I'm using an old grandfathered free google apps setup. So I don't have anything to really setup/configure myself. I know it's possible to do it with postfix and other mailing agents.

https://www.cyberciti.biz/faq/howto-setup-postfix-catch-all-...