The city of Los Angeles this week opened up its drive-thru COVID-19 testing sites to all county residents regardless of symptoms, and slots are filling up. For people who have made an appointment or those planning to sign up, a video from the L.A. Fire Department shows what to expect during the process.

People should prepare for the test, which is free, by not eating or drinking anything 20 minutes beforehand, as noted by an email they’ll receive confirming their appointment.

After driving up and waiting their turn inside their vehicle, the test taker will have to confirm their identity with personnel before receiving a bag containing a swab.

The test taker must cough into their mask three to five times to bring up secretions from their lungs. They then must take the swab and rub it inside their mouth: on the left cheek, right cheek and the roof of the mouth, near the throat, for 10 seconds each.

The swab then needs to be carefully placed, swab head first, into the liquid-filled tube provided in the kit. The test taker must screw the top of the tube back on and shake it to mix the sample with the fluid before putting it back in the bag.

Personnel can then retrieve the kit from the test taker.

The oral swab process may vary slightly, but more specific directions will be provided at the testing site.

Turnaround times of results will also differ. According to the city, test takers should expect to receive them within “a few days” via email or phone call.

As of Saturday, testing for asymptomatic L.A. County residents appeared to be fully booked.

On Friday, Mayor Eric Garcetti said slots for the next week should become available soon. He encouraged those seeking a test to check the website throughout the day.

According to the mayor, the dozens of city-run testing locations can take up to 12,000 people a day: 5,000 for those with symptoms, 4,300 for front-line workers and 3,000 for people without symptoms.