Heh, I know the feeling.
The good news is that you don't have to set up the DB. The one-click install will do that for you. Even if you haven't actually set up a database hostname for access or anything, there will be fields that you fill out in the one-click process that will set everything up.
The only thing you have to do first is to add your domain or sub-domain as a fully-hosted domain in the "Domains>Manage Domains" section of the panel.
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