While on a call, tap Add call.
Enter the 10-digit phone number and tap the Callbutton.
Note: To dial a number from the contacts list, swipe to or tap the Contactstab.
Scroll to and tap the contact name.
Tap the preferred contact phone number.
After the second call connects, tap the Merge calls button.
The conference call is now initiated.
Note: To end the conference call, tap End.
To end just the last call made, tap End last call.