another good one I like to use for important accounts: use uuidgen to generate a new uuid and use gmail's feature of ${username}+${uuid} @ gmail.com (and if you don't want to use gmail as primary, you can have it forward to protonmail or wherever.

This makes your login username also be a non-guessable unique password per service. You'll know who sold your email (or who got data breached) by what your incoming address is. And if your email does get leaked, nobody will be able to guess your email for other accounts, preventing brute force attempts and password reset phishing shenanigans.