For people who wear glasses, the biggest trouble in winter comes from the fog on their glasses: from outdoors to indoors, nothing can be seen in front of the eyes; Put on the mask and the world becomes blurred again... What to do? Try these methods (1) apply an anti-fog spray or gel; (2) use a cloth for anti-fog glasses; (3) use a lens anti-fog coating process; (4) apply shaving cream; (5) apply soap; (6) remove the glasses from your face and move them down a little while wearing them; (7) check that your clothes are obstructing air flow; and (8) avoid storing your glasses in cold environments.

Source: Beijing Municipal Education Commission