I'd advise using an email aliasing service (i.e addy.io) and a locally available password database (i.e keepass) synced across your devices via syncthing to protect your actual email address from leaks and to keep your passwords out of the cloud respectively.
Other than that, limit your number of online accounts to reduce number of potential weak links. Use cash to pay for stuff when possible. If you absolutely need to consume mainstream social media, do so via libre frontends like Redlib for reddit and invidous for youtube. Basically, give up any semblance of convenience.