Activation through the website
In order to activate your Product key or Gift card on the Nintendo website, follow these steps:
1. Log into your Nintendo account (You can create one here).
2. Go here for quick access to the Nintendo Product key and Gift card redemption page.
3. Simply paste the provided code into the designated area and press the Next button.
Activation through the console
1. Select Nintendo eShop on the HOME menu to launch it.
2.Select an account on which you would like to redeem the code.
3.Select Redeem Code on the left side of the screen and then enter the provided 16-character code.