Adding a menu to the top of the site

I would like to add an additional menu area to the very top of the site.

Ideally I want to include a link to social media icons and a login/register link.

I was looking at this tutorial but I cannot figure out where in the functions file the 2 menu locations are created.

What do I need to do to add a third menu location to the GDF theme.
http://www.wpbeginner.com/wp-themes/how-to-add-custom-navigation-menus-in-wordpress-3-0-themes/

OR is there a plugin I can use to do this?

Thanks