If you are already logged in, you won’t be able to view the login forms. Administrators will be shown a warning message, but regular users will not display any signs.
Admin Info: The Login Form will not be displayed if you are already logged in.
In order to inspect the login forms and check their look, log out of your present session or open a new browser window in incognito mode. This will let you view the login forms as they would appear to people who are not logged in.