First, create a bowler with maximum Strength, 13 points on Accuracy, and the remaining 6 points on Curve. Also use a ball with a weight of 16 lbs. During a game, turn the spinning of your ball to 100%. Aim with the red line exactly on the right edge of the third arrow from the right, as indicated below:

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Press X only once and let the bars totally fill. Your player will throw the ball all by himself and you will have a 100% strike all the time. if you do not have a strike, then aim slightly to the left or right until you find the correct spot.