You may never rid yourself of getting excited when a big buck appears, If I did... I would quit hunting!
Here's a little tip and believe me this works with practice!
Run for 2-3 minutes and get your heart rate up. Then, immediatly take aim at a fixed object while trying to calm yourself down. Focus on both your breathing and gun handling actions. Over time, you will learn how to gain better control as you aim.
Good luck!!!
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