Press L, then type "/cheatcheat" and press Enter. Now, you can use the codes given below:
Hitler mode: /hitlermode
Astar path rendering: /astar
God mode, infinite ammunition and flight mode: /ac
God mode: /godmode
Arrival point rendering: /arrival
Invisibility: /invis
Flight mode: /fly
Infinite ammunition: /ammo
Enemy field of view: /fovs
Win current mission: /winmission
Lose current mission: /losemission