If you are actually looking to modify the game files yourself, I have included a tip at the bottom on how to manually enable cheats.
Launch the trainer before the game and run it with administrator privileges to ensure it can modify the game's memory. 9 trainercom igi 2 better
Want to practice your sniping or learn enemy patrol routes? God mode lets you study the map without dying. If you are actually looking to modify the
: Prevents guards from sounding sirens even if you are spotted. 9 trainercom igi 2 better