Things You'll Need
Instructions
Select the Pokemon you want to clone in Fire Red and place it in your party.
Go to any Pokemon Center and head up to the second floor. Talk to the attendant to initiate a trade with another player.
Connect the link cable from your GBA to another GBA with any Pokemon version. Make sure the other GBA game is powered.
Select the Pokemon you want to clone in Fire Red when the attendant asks you for the Pokemon you want to trade. Select any Pokemon for the other version.
Turn off the power on both GBA before the trade process is completed. The screen should read, "Saving...Do not turn off the power" when you turn off your power. This step is the most crucial as the glitch occurs here. Be careful as misuse of this glitch can corrupt both game files.