Although scientists are quite clear about the importance of social distance and wearing the mask in order to prevent the Corona virus from spreading, and this is repeated by public entities, the reality looks different.
Many people either don’t keep distance or wear the mask right under their nose (sorry, but that doesn’t look cool, nor is it effective). What can you say if you end up with someone like that around you?
Tarts távolságot, légy szíves
Távolság is the important word here, it means distance. Légy szíves makes the sentence simply more polite, since you surely want to stay respectful. You can translate the whole sentence as “Please keep your distance”.
PS Facemask means szájmaszk