I've been stingy about that for a long time. FB doesn't have my phone number and I disabled the email address I used to sign up. I delete all my cookies often and use different browsers and turn off and reset my modem to get a new IP address.
I have no apps on my phone, don't use iCloud, and don't use the native "Contacts" app, I made my own for that.
I know I'm still being tracked, but not as much as most and I don't think FB could ID me right now with photos they have.