How do I connect a domain name I bought at Squarespace with a Commerce plan I just subscribed to

I bought a domain name here at Squarespace: image-magic.org

I just bought a Commerce plan here. 

How do I connect my domain name up with that plan ? 

I read the Help instructions, which talked about going to the domains page, clicking on the domain name, and getting a popup window that would let me connect it up. No popup appeared. And, yes, popups are enabled in my browser. 

The Help was, to say it kindly, opaque. 

Anyone have some simple instructions ?  It would be much appreciated. 

-- stan krute

I figured this out by just wandering around trying things. The instructions are indeed terrible. They leave out all sorts of steps that eventually get you to where you can click on "Move Domain".

I should have taken notes, but I'm a bit too busy these days. I'll do that the next time I go through the process.