Open up your Steam library.
Right click The Stanley Parable and click Properties.
Select Launch Options. In the text box that appears, type -console (or -dev console)
Launch the game as normal.
Another way is to open up the config.cfg with a text editor, then search for "toggleconsole" and replacing it with a key in case tilde (~) doesn't work.
Save, then go in-game and enable the console from the Options. Otherwise, search for "con_enable" and set it to 1 and then save.

hideous - Opens up a random page of the Team Fortress 2 Wiki.

bark - Whenever Stanley uses the action button (E or primary click,) you will hear a barking sound instead of the normal key-pushing sound.

raphael - In place of all dialog, the Narrator simply says "Stanley." "Stanley" is also printed in the console whenever dialogue would normally be spoken.

sv_cheats 1 - Normally enables server cheats, but instead, teleports Stanley to the Serious Room and Serious Ending. In the demo the console prints "Why????", but doesn't take the player to the Serious Room. Staying in the Serious Room and repeatedly entering the command will cause the narrator to "go shopping for another table." However, if you enter the command before loading or starting a new game on the main menu -- it will display the "Why????" message - now allowing for commands such as noclip and impulse (100, etc) - The game is now susceptible to most -- if not all HL2/Portal 2 console commands.

imabird - Float gently into the air, as in the Mariella Ending. Flying does not allow Stanley to overcome any obstacle, door or window that would normally block Stanley's progress on the ground; it's merely an aesthetic effect.

facepunch - Replaces all world textures with the Facepunch logo printed on top of them.

impulse 100 - Enables/Disables a flashlight.

noclip - Toggles clipping On/Off - *CAN CAUSE CRASH!!* - Be careful of what you fly through!

thirdperson - Sets a third person view - showing a purple block shaped character model lying on the floor as you move about.

firstperson - Sets the view back to first person mode.

Secret - Plays a special song when the credits roll in the Freedom Ending or when you select the Credits option from the Main Menu.

map blockbase - Teleports the player to the Minecraft demo, as seen in the Games Ending.

map freedom - Teleports the player to the scene just after the Mind Control Facility is turned off, in the Freedom Ending.

map map - Teleports the player to the last sub-ending of the Confusion Ending.

map map1 - Restarts the game.

map map2 - Teleports the player to the Mind Control Facility (as if they had taken the elevator in the Boss' Office.)

map map_death - Teleports the player to the Museum Ending.

map map_one - Teleports the player to the first loop of the Confusion Ending (in Stanley's office, after the Narrator restarted the game in the Monitor Room.)

map map_two - Teleports the player to the room below the Maintenance Room, the beginning of the Confusion Ending.

map testchmb_a_00 - Teleports the player to the Portal demo, as seen in the Games Ending.

map thefirstmap - Teleports the player to the second loop of the Confusion Ending.

map theonlymap - Teleports the player to the fourth loop of the Confusion Ending.

map zending - Teleports the player to the Zending.

map seriousroom - Teleports the player to the Serious Room and repeats the narration from the last time you went there. If you didn't input sv_cheats at all, it proceeds like normal.

ent_create_portal_companion_cube - Creates a Weighted Companion Cube, from Portal, at the place you're looking at. The string for picking up/dropping doesn't exist.

ent_create_portal_antique_cube - Creates an "Old Aperture Science"-style Weighted Storage cube, from Portal 2, at the place you're looking at. The string for picking up/dropping doesn't exist.

Bind 3 "Create_Flashlight" - Creates a Flash of light at the current cursor position.

bind 5 "ent_fire !picker unlock; ent_fire !picker open" - Point at any door with a handle, and press 5 and it'll open; even random environmental doors and doors closed by the narrator. Beware as this cheat may cause unintened game crash.

bind 6 "ent_fire !picker unlock; ent_fire !picker close" - Same thing as above, but with 6; closes any open door.

bind 4 "fire_rocket_projectile" - Press 4 to fire a giant missile shaped like the word ERROR. Stanley can actually "die" from this, and will force the game to to the beginning of the map you are currently on. This is inherited from the Source Engine itself, on which the game is based.

ent_teleport player - Teleports the player to wherever they're looking within the map. You can get stuck doing this; use at your own discretion.

bind "r" "ent_remove" - The player can delete doors.

host_timescale X - replace X with any number between 0.1 and 10.0. This is used to slow down the game speed in the Source engine, but without cheats here it just sets the speed of the Narrator's talking. 1.0 is the default setting.

http://thestanleyparable.wikia.com/wiki/Console_commands , Steam

http://www.youtube.com/channel/UC8FafV9l-rYR25BIoS0Dr3w