A useful tool for Theme Building is Smarty Debugging. Go to Administration Menu -> System Administration -> Preferences -> General Settings and set “Debug mode” to Smarty Templates Debug. Remember to do this only for a local setup or a non-production site since a pop-up will be created with a list of Smarty variables available.

It is a general rule that most Smarty variables listed by the Smarty Debug popup when the home page is loaded are available for use inside the theme.html. In simpler terms, when you load the home page, most Smarty variables from the popup can be used throughout the site as a Smarty tag embedded in the theme.html file.