Open up the file Hitman.ini, which is located in your Hitman game directory.
 Add the line

 enableconsole 1

 Then during gameplay, press [~] and type in the codes:

 god 1          God mode
 giveall        All weapons with max ammo
 infammo        Unlimited ammo
 invisible 1    Invisibility

 Use [Tab] to scroll through all the commands

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 To get access to all missions, start a new game and name the character

 Kim Bo Kastekniv

 (the code is case sensitive)