legally, what do I need to do to start my own home daycare in California?

I would like to start my own daycare business so that I can work at home. I have a nice house with pleanty of room and I have no idea where to begin. I live in shasta county, if that makes any difference. I would like to know every detail, step by step, of what I would need to do to be able to operate a business like that from my home. do I need some sort of license?