Instructions
Insert your copy of "Fossil Fighters" into the Action Replay device, then insert the device into your Nintendo DS. Turn the console on and let it load the Action Replay main menu.
Tap the "Codes" option on the main menu, then tap the "Add New Game" option. Type "Fossil Fighters" as the game's name by tapping the appropriate keys on the virtual keyboard. Press "Start" to proceed.
Press "Start" a second time when you are prompted to add the game's ID code. The Action Replay will have this filled in for you automatically, so there is no need to alter it. When you press "Start" this time, the game is saved to the Action Replay and you are brought to the "Fossil Fighter" code list, which will be empty.
Tap the "Add New Code" button. Name the code with something that indicates what the code does. Examples of this are "Infinite Health," "Unlimited Ammo" and "Invisibility." Press "Start" to proceed.
Enter the code exactly as you see it in your code resource using the virtual keyboard, but do not add the spaces between characters because these are added automatically. Press "Start" when you are finished typing the code. Repeat this process for each code you wish to enter.