The theme has three menu locations: Primary (2), Secondary (1) and Social Links Menu (in the footer).
You can create menus in WordPress by clicking Appearance > Menus in your WordPress admin area. Click on create a new menu to create a new menu (eg. Main Menu). Add the menu items from the left panels (You can select Pages or Categories).
Scroll down to the bottom where Theme locations and check Primary (or Secondary).
Social Links menu
To create a Social Links menu item (it’s works with our themes), use the tab Links (Edit Menus), example:
Navigation Label Twitter