How do I set up a language school in California?

I am considering setting up my own language school after working for one for many years as a teacher. I would like to purchase a domain, and create a website. Classes would be mainly at the students´ home or business. At first it would just be me teaching. How can I open this business legally in California? Do I need to register my business? Do I need to be self-employed and pay taxes? What are the steps to follow? Please advise.
Thank you very much.

see the link;

http://www.sos.ca.gov/business/filings.htm

you will most likely be a sole proprietorship.