1 - First press ENTER to get the message line.
2 - Press + and enter one of the following codes.
3 - After entering the code press ENTER to activate the code.

To deactivate a code just enter it again

Code - Effect:
+ATM = Gives you 1000 metal and energy.
+IWIN = Causes you to win.
+SING = This command makes units "sing" when given orders.
+ILOSE = Causes you to lose.
+RADAR = 100% radar coverage.
+VIEW# = Lets you see how much metal and energy a player has.
+DITHER = Dithering instead of line of sight.
+CDSTART = Starts CD Music.
+NOMETAL = Drops your metal to 0.
+NOSHAKE = Stops explosion screen shakes.
+NOWISEE = Full map and disables line of sight.
+NOENERGY = Drops your energy to 0.
+HALFSHOT = All weapons do half the damage.
+CONTOUR# = Displays a 3D contour, # = 1=15.
+CONTROL# = Lets you to control a different skirmish AI.
+SWITCHALT = Allows you to switch between squads with alt+# keys.
+DOUBLESHOT = All weapons do twice the damage