Where do I register my Activation Code for Heavensward?

[Risvertasashi]

This is a question that is more complicated than it needs to be because multiple codes are involved and the process depends on both platform and region.

But in short... the mogstation part of registration hasn't opened yet; you cannot register your final code (if you can even get one) on mogstation yet.

Now as for how to get to that point, see the above posts. Your location says Washington, so if you bought the US version on the US site: Use your code on the website included on the email. This will give you a second code. Save this second code somewhere, you can't do anything with it yet.