Instructions
Turn off your Nintendo DS console and insert the Action Replay device into the cartridge slot on the Nintendo DS.
Power on the Nintendo DS. Press and hold the "A" and "B" buttons immediately after turning on the console. You will need to use your right thumb to cover both buttons.
Wait for the Action Replay introduction screen before pressing and holding the "Start" and "Select" buttons with your left thumb. Your right thumb should still be holding down the "A" and "B" buttons.
Hold the four buttons down for 10 seconds. You will know if you have done this correctly if the Action Replay introduction screen does not change to the main menu over the 10-second time.
Release all four buttons when the Action Replay main menu finally appears. Scroll down to the "Games" option and select it by highlighting the "Games" option and pressing the "A" button. If you do not see any games or codes within the Action Replay device, your Action Replay has been reset.