Summary: Covering your face is good, but new research suggests that how you do it is important. Many help prevent the spread of the coronavirus, but some are not as effective as others. Reporter Aidin Vaziri has the details. | Unlimited Chronicle access: sfchronicle.com Related episode: Do Face Shields Work? (Aug. 5, 2020) Learn more about your ad choices. Visit megaphone.fm/adchoices
