While there is not a dedicated field to enter your social media information, you can add links to your social media or include your social media handles in the About section of your profile, or under Other Experience. Both of these fields are editable from Your Profile.
These changes will only be reflected on the profile to which you’ve made changes. To make changes on any other profiles you may have, scroll to the top of the Your Profile page. If you have multiple profiles, you will see a profile switcher showing your personal profile and/or any represented profiles you have.
Click on the switcher to select a profile, and you can edit your About or Other Experience sections on each profile.