Hi dhavex,
I’m no expert and you’ll probably get better answers than what follows, but here is what I’ve done to get a favicon on the The Box theme.
First, you should probably do this with a child theme, of course. With an FTP client, you should put your favicon.ico file at the root of your child theme, here:
wp-content/themes/the-box-child/favicon.ico
Next, you should make a copy of the original header.php file (the one that comes with the The Box bundle), and add the following line between the two <head>
and <meta charset="<?php bloginfo( 'charset' ); ?>">
existing lines:
<link rel="shortcut icon" href="<?php echo get_stylesheet_directory_uri(); ?>/favicon.ico" />
By then, you should be done (just change the file name of your favicon file according to your settings).
HTH… Best wishes,
Christian