I know how you feel. I was in the same situation. It is the same as memorizing pit music. Actually it is slightly easier(but memorizing drill with it makes marching overall more difficult)because you don't have as much to memorize. The best thing to do is just make sure you are mentally prepared and know your rudiments...practice playing open!!
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Caption Head for The Wolves Drum & Bugle Corp
-2008 Div. III 5th place
04-Dacula HS Pit
05-Dacula HS Pit
06-RVRHS Indoor Drumline:Pit
07-RVRHS Drumline: Bass2
07-RVRHS Indoor Drumline: Bass2