For powerful and accurate casts, grasp the rod normally, with your index finger around the trigger portion of the rod grip. Then rotate your wrist until the reel handles point upward. This puts the first knuckle of your index finger (where the finger joins your palm) on top of the rod grip. In sports, almost every handgrip that requires power uses this knuckle position, be it on a baseball bat, golf driver, or tennis racket.
Some people cast with the handle to the side, but then the upper surface of the rod grip, which lies in the same plane as the casting stroke, is unsupported. That saps power. The thumb is also unsupported, making precision spool control difficult.
 POWER The knuckle of your index finger is on the top of the grip and the rod is held firmly for a consistent stroke throughout the cast.
 ACCURACY The thumb rests on the lowermost edge of the spool frame. Rock it gently inward against the spool for pinpoint placement and to prevent backlashes.