I assume you're looking for a more specific answer than "Quit turning your hand so much", right?
It's really that simple though. Really concentrate on your release. Practice finishing with your thumb pointing straight up. If it's past 12 after your release you've gone too far. A lot of people that spin the ball have the habit of "chicken winging" the ball. So check your elbow position. If it's not close to your body, work on that. When you practice, throw whole games where you don't turn your hand at all, stay behind the ball the entire time rolling the ball end over end.
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What are you gonna do? Beat me with your Jesus stick?