I'm trying out the Pro Sites plugin to see what it can do. I've watched all the videos and installed and set it up from the detailed instructions at https://premium.wpmudev.org/project/pro-sites/#usage, but I'm left wondering where to go from here. I don't know how WordPress is expected to work for a new user. What are the main links I need to provide to enable them to sign-up for a blog? How do I set-up WordPress Multisite itsel, rather than just the Pro Sites plugin?