First, thank you for the help and the patience! I've set up a fair share of domains and hosting accounts over the past five or six years with other hosts, but right now I feel like a complete newbie because there must be something very fundamental that I am just not understanding.
"If you're going to host a domain here, make it SUB.MYDOMAIN.com. Make it Fully Hosted . . ."
Ok, when I try doing this using mysubdomain.mydomain.com I receive an error that says: Can't add domain: you don't have permission to add to mydomainname.com.
Just to be clear, let me restate my understanding using widgets.com as the domain and specifying that there are no existing domains or subdomains created yet at all.
Starting from zero, I need to create a fully hosted subdomain as SUB.MYDOMAIN.com.
So, I am typing in widgets.widgets.com.
Is this right? When I do this, I receive "Can't add domain: you don't have permission to add to widgets.com."
My understanding is that I create widgets.widgets.com, then create a mirror domain widgets.dreamhosters.com that mirrors widgets.widgets.com. Then, I should eventually be able to type in widgets.dreamhosters.com and get a preview of the site. Once things are good, I can go to my registrar and set the DNS for ns1.dreamhost.com (etc.) and widgets.com will eventually show what is at widgets.dreamhosters.com? Right?
But, I can't even get widgets.widgets.com started.
Should I be creating widgets.com, then widgets.widgets.com, then mirroring, etc?
I think there are two things (aside from the error) that are making my brain seize up. First, is the idea of creating a subdomain before establishing a domain. The system doesn't seem to like it either, but doing exactly that is what I've read in the replies here as well as the Wiki articles. Second, is that I've always only thought of a domain name exclusively within the context of a domain name being a user-friendly pseudonym for a less memorable IP address/path. I've never worked with the idea of creating domains on the hosting server, only directories, and then specifying "add-on domains" so the server will know which directory contains the files for the domain. It seems that with Dreamhost, I need to be thinking of the subdomain as a name for the directory where the files associated with the domain name will reside and therefore the subdomain name itself on the server will be the method of identifying what directory to serve from when a request is made for that domain name. So when I've encountered settings that I've made at other hosts that are called things like "ad-on domain" or whatever that allow you to basically say, "when the people want widgets.com, give them what is in folder X", it's just a really dumbed-down way of creating a subdomain and Dreamhost just uses grownup language? Is this right?
Thanks again for any guidance or direction.