What do I need to do with my plates?
Keep your plates. You can either transfer them to a new vehicle or cancel and destroy them.
Is there anything else I need to do?
You will need to notify the DMV that you sold the vehicle to cancel your registration.
Don't cancel your insurance until you've canceled your registration with the state. Once that's done, contact your insurer to remove the vehicle from your policy.
Submit your Registration Cancellation Receipt to your local assessor to stop your excise tax.