When playing the game activate the cheats by pressing SHIFT + ALT + D, then use any of the codes. Repeat for each code you want to use.
Code - Effect
SHIFT + ALT + T - FPS and computer usage
SHIFT + ALT + F - Framewire
SHIFT + ALT + 4 - Get 5,000 cash everytime
SHIFT + ALT + W - Level target and other info
SHIFT + ALT + 1 - View 1
SHIFT + ALT + 2 - View 2