Andrew Klavan had some very wise advice for aspiring writers on his podcast last week. Get a job to pay the bills, then write as much as you can (freelance, part time, whatever) until you can make enough money writing that you can leave your day job. I have seen many content creators follow this exact plan, and are now very successful.
This is not the path I am following, of course, but being a professional writer is not my goal. This is my hobby. :)