Our Beloved Prophet Muhammad ‘saw’ always smiled when he was with his sahabah and even when he was taunted. So smile during good times or bad.
During these trying times of covid-19 crisis, we are advised to stay home and practise social distancing which means no hugs, no hand shakes and practically there should not be any physical contact with others. However that does not mean that we need to be distant with others spiritually. The best sunnah to practise during this catastrophic times is just smiling. Although most of us will be wearing masks but when we smile, our eyes will light up and others will know that we are smiling. So smile;) Its sunnah!