Set up your social networking service accounts.
On the start screen, swipe left, tap the social networking app you want to sign in to, such as Facebook, and follow the instructions shown.
To download more social networking apps, tap Store.
Tip: When you sign in to an account, the contacts in the account are automatically imported. To choose which accounts show up in your contacts list, on the start screen, tap People, swipe to contacts, and tap > settings > filter contact list.