My question involves landlord-tenant law in the State of: California

I have two lodgers in my home renting separate rooms and I wish to evict one of them. We don't really get along and I am tired of constantly butting heads with this person.

What is the process I need to follow to successfully evict this person?

Am I better off with a Lawyer and what would that cost?

Any help here would be greatly appreciated and thanks in advance for your feedback!