Tips for starting sharp?

[kbilla]

Fri night, BV, 3-whistle game. R throws the jump and I end up C. We transition once, and then back and on this transition A1 goes up on a break for a layup and B1 blocks it "off the glass". Nothing like the first whistle of the night being a bang-bang BI call. It took me a second but I got the call, wasn't too delayed and obviously the correct call. My question is this. It always seems like the first few times up and down I am in a bit of a fog, just settling in to the game, etc. Any tips for what you do to get a "mental warm-up", so when these relatively unusual things happen right at the start you are prepared for them?