Header Right widget area has one widget - Simple Social Icons.
Simple Social Icons
- Title: No title
- Open links in new window? Checked
- Icon Size: 40px
- Icon Border Radius: 0px
- Border Width: 0px
- Alignment: Align Center
- Icon Color: #666666
- Icon Hover Color: #ffffff
- Background Color: #ffffff
- Background Hover Color: #666666
- Border Color: leave on white
- Border Hover Color: leave on white
- Add the urls of your social media accounts below the settings.
- Click the Save button.
Note that the Background Hover color is changed by the theme when you change your link (accent) color in Appearance > Customize > Colors.