What to Do When Someone Catches You Staring at Them

This is actually a tactic taught to secret service agents and others who often have to follow or keep visual tabs on somebody without that other person knowing about it.

What happens when the person you are trying to covertly watch catches you looking at them? The simple answer is to start digging your nose while slowly averting your eyes. Yes, it is disgusting, and that's the point. Anyone would normally be embarrassed if they were caught digging their nose, so the fact that you're doing it so openly suggests that you are unaware of anyone else around you. The person you've been watching will be disgusted, perhaps, but they'll never guess that you are actually observing them.