Here’s my experience from being a member of clan [WAG] and [GOD]. Start out on balanced maps like de_dust, cs_italy, or de_aztec. Use standard pistol or deagle, and for main use mp5 (low on cas) or light rifle (ak or m4). Standard strategy you can probably get from people above. When game starts MOVE, don’t stay behind or rush in blindly, but move with your teammates or get them to move with you. As you get better start putting flash, vest armour, and grenade into your arsenal. Before then, if you suck, then you drain your cash and you probably die before you actualy make good use of them. Some people are really nervous in the game, especially when everyone has died excpet you and some other guy, so a lot of pressure, I solved this lil problem by practicing playing the game while listening to music, hence no sound, using only visual, this is a good way to get used to moving a lot and looking everywhere. Try it. Also, make sure you are really in a high state of energy when playing, like with a few cups of coffee.
That’s bout it,
Hope this helps