Traditional grip is unique among drum grip styles in that it's not a matched grip — that is, the way you hold the stick isn't the same for both hands. To play with a traditional grip, begin by raising your your non-dominant hand in front of you and turning it so its palm faces upward toward the ceiling.  Note — traditional grip was originally used by military drummers who found it difficult to drum with a matched grip while on the march. To maintain uniformity, the left hand was generally used to hold the stick with an upward-facing grip regardless of which hand was the drummer's dominant one. However, in a modern context, some left-handed drummers reverse the typical traditional grip and use their right hand as the upward-facing one. Your off hand is ready to play! Now, all you need to do is grip the other stick with your dominant hand in an overhand style just as you would for any of the matched grips above. You can use whichever grip is comfortable for you, but most find the typical American-style grip (or some minor variation on it) to be easiest.

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Write a summary of the previous text in Vietnamese:
Xoay lòng bàn tay không thuận của bạn lên. Sử dụng cách cầm úp bàn tay ở tay còn lại.