- copy the folder "cstrike" inside the zip

- open your "counter-strike" folder on your computer, normally it is located somewhere like this:
	C:\Program Files\Steam\steamapps\STEAM_ACCOUNT\counter-strike

- Paste "cstrike" folder from the zip into "counter-strike" folder. If done correctly windows will now ask if you 
    want to merge the two cstrike folders. Press Yes.

- Done! Start CS -> new game -> choose map -> de_dust2,  app! app! app! haha! nooo, de_racetownz! Yeees! :P.