I was told by our county, that I do not need a business license to have a home business, because I live in an unincorporated part of the city. (in Calif). I bake from a licensed kitchen, (rented space) but make some of the decorations at my home. How do I start the process to be a professional?

I'd think that you'd need an EIN at the very least, and to register for any local/state taxes. You'd probably need some sort of inspection/sanitation training from your local HD. And then liability insurance and some sort of incorporation.