create new site subsite in wordpress multisite by subscriber user instead of network admin

Go to /wp-admin/network/settings.php as a Super Admin and where it says “Allow new registrations” set it to one of these:

  • “Logged in users may register new sites” (no new users can register)
  • “Both sites and user accounts can be registered” (new users can register)

Both these settings allow logged in users to create new sites by clicking on “My Sites” and then “Add new”, which points them to /wp-signup.php.