Things You'll Need
Instructions
Place your Pokemon game into the Action Replay, which has a cartridge slot similar to the one on your Nintendo DS. Slide the game into the cartridge slot until it clicks into place, then slide the Action Replay itself into the cartridge slot of the DS.
Slide the "Power" switch to the "ON" position, to turn on the DS. Click the Action Replay icon.
Enter any EV cheats you wish to use at the Action Replay screen. For a list of codes for each Pokemon game, consult SuperCheats.com or Neoseeker.com. Make sure the code is entered exactly the way it is shown on the website, otherwise it will not work.
Load the Pokemon game by pressing the "Start" button, and select your game file. Most cheats should already be activated, but if not, press the "L" and "R" buttons to activate them.