The rule of awkward silence is simple: When faced with a challenging question, instead of answering, you pause and think deeply about how you want to answer.

But make no mistake, this is no short pause. You might go five, 10, or even 15 seconds before offering a response. Which, if you’re not used to doing it, will feel very awkward—at first.

Garrett Reisman, an engineer and former astronaut who left NASA to join SpaceX, described how Musk uses this technique in a recent interview.