One thing that would be great would be if people would throw on a mask if they have to go out while they're feeling sick. This is considered common courtesy in some places, but just isn't done much in the West. You could do so yourself even when not sick, and that presumably would help protect you from people who are sick (and are probably not masked), but I expect that will be considered socially "weird" after things go back to normal.

Continuing to wash your hands often and avoid touching your face (especially after touching things in public like door handles, elevator buttons, etc.) probably would help as well.

Agree that social distancing isn't really practical outside of the current situation.

But really, there are just a lot of things that you won't be able to avoid, at least not unless you want to stay at home more often than you used to rather than venturing out. Conference rooms at an office, crowded public areas, public transit, even lining up at a popular takeout restaurant... all of these things make it easier to pick up something from someone else, as virus particles in water droplets can linger in the air for quite some time.