and another tip
but now from a real pro :P hehe
some settings tweaks: i would set all settings as low as you can.. i have that.. my settings are lowest graphic detail highest gamma (i know it's sick) but! if you practiced with those configs you will see the enemies much better! try that!
and .. for precision you need good equipment.. Mousepad and mouse, i have here some of the best equiment you can get:
Mousepads : fUnc sUrface 1030
(i got that
) , Steelpad 4s/3s/4d, Icemat,Corepad,Everglide Riocchet, and many others
Mouse: Razer Viper
, Razer Boomer Speed/Control , Razer Boomslang 1000/2000, Logitech MX510 , Microsoft Intellimouse explorer 4.0,and many more...
if ya wanna know more (what i don't think
) just mail me..
and: I've played 10min with Fatal1ty ... he beat me 86 to 13 
Perhaps the boomslang
?