well quick reacions DO help a lot in this game, seeing how its a first person shooter
i'd say (this is what many others say and i tried it and its helped me out some) to shoot a gun at the wall, and see how the bullets move away from your crosshairs and remember that. then apply it to when you shoot so you're actually hitting what you're aiming at, which can be very frustrating when you aim at them cleary and miss. and also remember the "gay" spots that people always complain about.
for example on cs_office, the exit sign in the front stairs outside ct spawn, people camp on top of that, so check that all the time. behind the doors at T spawn, and so on.
and most of all, never get mad at people trash talking you, or just because you're sucking. if you take it in stride, usually you can pull out of your dumpy feeling and get back into high spirits and have fun again
hope that helps some
