Honestly, I don't think those are good instructions to follow. Those instructions have you physically copying portions of your WordPress installation into new locations, which is not required (and generally not desired) with the WP Multi Network plug-in.
The only things you really need to do to get the WP Multi Network plug-in working (in my experience, at least - I've installed and activated it on two servers at this point) are:
- Perform a complete back-up of your WordPress installation (database and files)
- Install and activate the WP Multi Network plug-in
- Open your wp-config.php file and comment out the following lines (if they exist in your wp-config.php file):
define( 'DOMAIN_CURRENT_SITE', 'example.com' );
define( 'PATH_CURRENT_SITE', '/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );
- Generate new "salts" for your cookies (this step isn't necessary, but it helps to ensure that lingering cookies won't mess anything up when you try to login) by visiting https://api.wordpress.org/secret-key/1.1/salt/ and pasting the new information in place of the old salts.
- Save and upload your modified wp-config.php file
- Go back to your Admin area and login again.
- Go to the "Super Admin" menu and click "Networks".
- Fill out the form to create a new network. Make sure that the "domain" does not include "http://" at the beginning, but it should be a full domain name (for instance, if you want to access the new network by visiting http://subdomain1.example.com/, you would enter "subdomain1.example.com" in the "domain" field).
- In the "path" field, enter a "/" (unless your current site is located at a different path, but most of them are located at "/")
- Click the "Create Network" button.
All of that said, I believe this plug-in is normally intended to create new "sites" in sub-directories (so your initial WP Multi-Site setup should be done for sub-directories, not subdomains) and the "networks" to be set up in either subdomains or completely different root domains.
In addition, if you are planning to use subdomains for your new "networks", make sure that your DNS and apache settings are configured to allow either the specific subdomains you'll be using or, ideally, wildcard subdomains.