domain mapping – wordpress.com to .org

I’m horrible at the technical terms, so bear with me! 🙂

When I was still hosting my blog at wordpress.com I had paid to drop the wordpress part of the domain. A few months after, I switched my blog to a self-hosted site at ww.wp.xz.cn.

Now that I’m at the .org site, I don’t want to keep paying the yearly fee at the .com site. What steps should I take to resolve this and still keep everything that was published before I transferred to self-hosted?

My guess was from the wordpress.com dashboard, go to settings > domain, then click delete under actions. I wanted to confirm this is correct OR find out what I need to do.