Assume aliases. Use Tor or other proxy routing. Write in a different style than your usual conversational tone. Redact, redact, redact again anything potentially identifiable. Set up domains with phony contact info. Pay for things with offshore accounts, shell companies, trusted international friends, etc. Generate your passwords with random alphanumeric character strings. Distrust *everything* coming over email, as this is one of the most common attack vectors. And for gosh-sakes, be paranoid about your security on the home front. If possible, do all your anonymous stuff from an OpenBSD box running the bare minimum of services.

When all else fails, call for support from your fans to go vigilante on anyone trying to hack your identity. This isn’t a game, it’s war, and those who try to play fair/nice end up getting hurt.