This is how you do it:
make a desktop shortcut, then change directory for it to (Ex.):
C:ProgramsCall of DutyCoDSP.exe" "+set thereisacow 1337 +set developer 1 +set sv_cheats 1 +set monkeytoy 0"
Then start the game with the shortcut
When you are in the game press "~" to get the console vindow.
Write this in the console window
God=Imortality
Notarget=Enemys wont se you
Note: If you change any files make sure that you do a back-up!