YoYoJam DarkMagic
Snap Start
 
To start a Snap Start simply hold the yo-yo in your throw hand. Place your thumb on the side in towards yourself, with your middle and index finger on the far side.
 
To snap it is a similar to how you "snap your fingers" to make that snapping sound. Push your thumb up hard against the yo-yo and your middle finger down the opposite way. Your index finger is mostly used to guide the yo-yo into the air.
Note: In the video the yo-yo is caught between the thumb and middle finger. This is just a fancy way to do this trick. First practice just spinning it, then move onto this to gain control of your snap start.
  If you have done it correctly the yo-yo should be spinning fast enough to return to your hand with a bind.
Note: in the video from the thumb mount, it is dismounted in a ripcord motion pushing into the string twice.

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