To avoid popping "P" sounds, subjects should always talk across the mike, not directly into it. This is counterintuitive because people naturally want to lean into a mic and talk directly into it.

Assume the gray area is the zone where air puffs out of the mouth during speaking. You generally DON'T want to put the mic in this area. That's because the air that puffs out when you say "p" can mess up a microphone. It's true that wind screens (the round ball at the end of a mike) minimize this problem. Regardless, it's good to keep the mic out of the line of breath.