First off, hit F12 to open the COMMAND box. You can tell this is open because in the empty box thing on the bottom of the screen should be the word COMMAND in green. Next, type IMAREALWEENIE and hit ENTER. Next, to put in a code, hit F12, type the code, and press ENTER.
MAKETHEMSTOPMOMMIE - Turns off enemy A.I. (Enemies won't attack)
ENEMIES - Shows enemy stats, kinda...
SPY - Show debug numbers
FPM - Frags Per Minute
[CTRL] [F3] - Kills all enemies that are in the battle and gives you the EXP, GOLD, and ITEMS you night recieve. *****THIS ONE YOU DON'T HAVE TO HIT F12 BEFORE DOING BUT YOU MUST BE IN A BATTLE*****