As a relatively new platform, we are constantly adding new features. We are currently working on the feature that allows users to add more social media buttons. Ideally, that feature will be available this year.
In the meantime, you can add links to your social media pages within the menu of the header and footer. Just click on either section and look for the “Configure Menu” button. That will open the menu editor. From there you can add the new link(s).