How to Skip a Stone

We asked a physics professor for the ultimate tips. (Adapted from here: http://nyti.ms/1Ui3Ke7)
  1. Throw at a 20-degree angle.
    So says Lydéric Bocquet, a physics professor at École Normale Supérieure in Paris. That’s what he calls ‘‘the magic angle’’ for a maximum number of skips.
  2. Choose the right stone.
    Bocquet suggests something in the range of 4 to 6 inches in diameter. A thin, roundish rock is ideal, but with enough velocity you can skip almost anything.
  3. Stand as a baseball pitcher would, with your body’s side facing the water.
  4. Nestle a flat rock in the crook of your index finger and sling it sidearm, flicking the wrist to give the stone a spin.
  5. Aim for at least 2 rotations per second.
    The spinning motion allows the stone to stay on course, providing what physicists call ‘‘gyroscopic stability.’’
  6. Trust that there’s something innate about the act.
    ‘‘Our bodies just know how to skip stones,’’ Bocquet says. ‘‘I don’t know why.’’
  7. Don’t overthink the effort.
    Chances are if you're reading this list, you've already failed this step. (Don't worry; we did too.)