How do you use game shark on 3DS?

To use GameShark on a Nintendo 3DS, you'll need to have a compatible version of the GameShark device. First, insert the GameShark cartridge into the 3DS, followed by the game cartridge you wish to modify. Power on the 3DS, and the GameShark menu will appear, allowing you to enter cheat codes for the game. After entering the desired codes, start the game, and the cheats should be activated.