The installation of the package is the same as with any other Joomla! component. Go to your site's back-end Extensions -> Manage and click on Browse. Locate the ZIP package and click on Upload and Install.
Read here how you setup the component before use for the first time.
When a user access for the first time PH Cloud, a default account is automatically created. Also the DAV server data are initialized, so the specific user will from now on have access to the server.