Guns:If you don't know which gun to buy well these are the guns you should:
First you should by the Ak-74 or M4A1.
Secondly save up and don't buy ANYTHING
Finally Buy the SCAR LIGHT(LIGHT NOT HEAVY)
If your gun has a Lot of recoil then shoot 1 bullet at a time or 3,2 or 4
If you rush always ALWAYS spray n' pray (This method is sometimes really.
If you ever see somone run up to a box and camp,just shoot the bullets will go through.
Egypt is the best man to rush in so i recommend you to.
S&D mode isn't really good,its preety much a waste of time if you want to level up and also E.M.
If you want to level up really fast and have to computers with CrossFire on both of them you can.
1.Make both accounts join the same room and se the kills to 150 and respawn to 0.
2.Use the character you want to level up the the other teams base and use your knife to kill the other play using left click
3.After the time is up you should gain 720+exp