Bring down the console with the Tilde (~) key and enter the cheats.
*NOTE* Listed cheats will cause the game to display your name as "CHEATER".
Lists available skills, add a Skill Name after cheat and it tells you the skill number.
CheatSkill [Skillname] [Amount]
Use to set your skill number to whatever. Example = "Cheatskill skshooting 99".
(supplied by: Knightmare27)
Type enter_dev_mode into the cheat console. Press [Enter] then type shop. You will be transported to the shop with everything and then transported back to your game.
Type ImmortalCheat 1 into the cheat console.