I wear a mask whenever I come within two metres of another person. If you come within two metres of another person, you should be wearing a mask.
People are infectious with the virus for four days before symptoms appear. The most common transmission occurs not from surfaces or hands, but from breathing. It surprises me that more in my local community are not wearing masks – in other countries, it is default behaviour to wear a mask even if you have no symptoms. Given that there are now projections for 50,000 to die in Australia, you could save a life by wearing a mask.
A four day incubation period with no symptoms. Any mask is better than no mask. Act as if you have the virus.