There's almost never a need to crouch with AWP. It takes time and reduces your movement speed. It just makes you vulnerable. And there is no accuracy bonus. Standing still the AWP has perfect accuracy at any range.
And on another note, flickshots are the way to go with the AWP. I'd recommend turning off mouse acceleration so you can get it perfect almost every time. This allows your wrist movement to be the same for every shot. It takes some getting used to, but it's by far the best way to improve your AWPing.
Look up Sp00n's (from Team Audacious) frag video for a good look at some amazing and consistent flickshotting AWP action

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