The option to book an appointment went live Wednesday, a day before the age group becomes officially eligible.
Previously, people ages 50 to 64 were only eligible to receive a COVID-19 vaccine (in most California counties) if they had underlying health conditions or worked in a high-risk sector like food or emergency services.
To make an appointment, go to myturn.ca.gov, fill out your information and enter your address. The website will show you if there available appointments near you.
You can enter different cities or ZIP codes into the MyTurn site to see if you there are availabilities elsewhere. However, a word of caution from the state before you book a COVID-19 vaccine appointment far from home:
As California expands COVID-19 vaccine eligibility, here's where to look for an appointment
"Your appointment could be cancelled depending on the requirements set in the county you are seeking a vaccine. Each county sets their own geographic requirements and most limit vaccination to those who live or work within the county. So before booking a vaccine appointment outside your county of residence, check the other county's official government website to make sure you are eligible to be vaccinated in that county, otherwise your appointment could be cancelled."
California officials said the state can administer 3 million shots a week now, and Gov. Gavin Newsom has predicted that maximum capacity will climb to 4 million by the end of April. But supplies have limited the effort so far to 1.8 million shots per week, a figure that is expected to increase to 2.5 million per week in the first half of April and then 3 million by the end of April, when everybody 16 and older will be offered the vaccine.
Santa Clara County has been told it will get 58,000 doses this week, health officer Dr. Marty Fenstersheib said, but the state will begin allowing about 400,000 more people between 50 and 64 in the county to sign up as of Thursday, in addition to the current backlog.
"We don't have the vaccine, and we are concerned," Fenstersheib said.
Among the methods officials are employing to reach underserved communities are vans used as mobile clinics that travel to hard-hit neighborhoods and provide on-the-spot vaccinations.
In California, mobile clinics are helping vaccinate farmworkers who may not have transportation to larger vaccination sites or cannot navigate the state's online portal. Los Angeles also plans to have 10 mobile vaccination teams.
The Associated Press contributed to this report.
VACCINE TRACKER: How California is doing, when you can get a coronavirus vaccine