Now is the time to register your Nintendo Network ID, so you have the name you want for the Nintendo Switch. Even if you think you have a Nintendo ID, you probably don't have one that will serve as your online name on the Nintendo Switch.
It's like your PSN ID or Xbox Live ID, but for the Switch. You can register it now to get the Nintendo Network ID you want so you won't have to spend time doing it when setting up your Nintendo Switch.
Many gamers already have a Nintendo Network account and even a nickname for that account, but most of us don't have a Nintendo Network ID. If you want to reserve your name for the Nintendo Switch online service, you need to set up your Nintendo Network ID now.
How to register your ID for Nintendo Switch
The first thing you need to do is sign in to the Nintendo Account you already have at accounts.nintendo.com .
If you haven't used a Nintendo Account in a while, you may need to create a Nintendo Network Account. You can link it to your Facebook or Google account. If you're setting up a new Nintendo Network account, be sure to set up a password and verify your email address.
If the user ID is not defined, you must save it.
Now that you are logged in, look and see if there is anything in the User ID section of your Nintendo Account. There is a good chance that there is nothing in this area.
Choose your Nintendo Switch ID.
Click Edit, then enter the Nintendo Network ID you want to use as your online presence on Nintendo Switch and other consoles in the future. This will lock it down so you can use it and don't lose it to someone else.
Success. You have registered your Nintendo Switch ID.
If available, you will see a screen telling you that the user ID has been set. This will lock it down so you can use it and don't lose it to someone else.
It's still very early, so you can register many common names, and chances are you'll get your account now. If you wait, you'll probably be stuck with alternate numbers or spellings. Even if you don't get a Nintendo Switch on day one, it's a good idea to reserve it now.