This simple tutorial will help you create a Log In/Log Out menu link that will display a link to the login page when the user is not logged in and a link to log out when they are logged in.
This has now been incorporated into the plugin as a standard feature – all you need to do is add a login link to the menu and give it a custom class of “wpmem_loginout”. See documentation on this feature. This tutorial remains primarily for informational and educational purposes OR if you’d simply like to customize the login/out menu item.