Well firstly, if the domain and/or sub-domains do not already appear in the list at Domains -> Manage Domains in the panel, you will need to add them to the hosting system by clicking on the Add New Domain / Sub-Domain link on that page.
Once this has been done, you should see sub-directories in your home directory corresponding to each of the (sub)domains you added. By default these sub-directories will have the same name as the domains. For example...
These sub-directories are the web-directories for your domains and/or sub-domains, this is where you need to upload your site files.
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