Step 1: Create the Menu: 

1. Create a new menu (dashboard > appearance > menus) called social icons or something similar.
2. Hit the “create menu” button.

Step 2: Add Social Media links

1. Add your social media links using the custom links tab from left side, should look something like screenshot below
2. Next select “social” from menu settings, you find the menu settings below menu items. 
3. Once you have added the custom links and updated the menu settings, hit the “save menu” button.