While playing counter-strike, press " ` " to enter console. For quick buy of a Mp5Navy, Primary ammo, secondary ammo, kevlar vest & helmet. Type the following:

Bind h "buy; menuselect 3; menuselect 1; buy; menuselect 6; menselect 8; menuselect 2;"

To quick buy other primary weapons just replace menuselect 3 and menuselect 1 with the following:

Ak-47 = menuselect 4; menuselect 1;
Commando = menuselect 4; menuselect 2;
SteyrAug = menuselect 4; menuselect 4;
Carbine = menuselect 4; menuselect 3;
Scout = menuselect 4; menuselect 5;
Arctic = menuselect 4; menuselect 6;

After binding the desired key, during gameplay at the beggining of the round press the binded key to instantly buy all items and make sure you cancel the buying mode after all the items are bought.

With this cheat you can position yourself ahead of the others in the game !

Tip: Just make sure you have enough money. Also works with all items in the buy code.