Talk to your friends, colleagues and neighbors. Get their referrals.
Drive around your neighborhood and see who is currently doing projects in your area? Take pictures of the builder’s boards.
Visit your town hall to check the blacklisted.
Go online. You need to scout Houzz, Angie’s list, Buildzoom, Handyman, Porch, Thumbtack, Homeadvisor. You can do one or all, depending on the level of your perseverance.
By now you should have the shortlist of a dozen of those that you will need to talk to to find out if they take on the type of project that you are planning. Run the numbers of their licenses by the California Licensing Board:https://www2.cslb.ca.gov/OnlineServices/CheckLicenseII/CheckLicense.aspx
You should have at least 3 in the list that you will go into more detailed negotiations on what needs to be done, when and within what budget.
Have a break. You deserve it.
This is also a good time to have a floor plan ordered if you do not have one yet, and have no plans to hire a designer or architect. Welcome to use https://blue-sketch.com/shop/
Blue Sketch will draw the floor plans using common floor plan drawing tools. Kitchen cabinets, stoves, bathroom fixtures, washing machines etc. are shown as icons. The icon marks the place and purpose of a fixed furniture. All sizes and dimensions are approximate as they draw the floor plans based on dimensions received from you, and thus can not guarantee any specific accuracy. But these floor plans will be a good help when talking to contractors.
If you are ready to do it yourself, welcome here https://www.livehome3d.com/mac/live-home-3d
Live Home 3D helps you draft detailed 2D floor plans and automatically build the structure in 3D. You can trace the imported floor plan or start from scratch using the program smart tools. Design and decorate the interior by optimizing the furniture arrangement and making smart color decisions.