I think you did not know that DH provides mediawiki. You can install mediawiki by simply clicking some buttons on the menu. The current version of mediawiki that DH is using is 1.9.2
I guess the procedures are same for most of the web server providers. Get a domain. Install mediawiki. Set up database if necessary. Upload files.
If you already have a domain and want to host in DH, you can do it by setting up the DNS.
It takes some time for the DNS change to propagate.
If you do not have domain, get one from DH. All the hosting plans include a free domain name.
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