Tap the Home Button > the Apps icon > Settings > Second screen.
Set when the Second screen is enabled and what it displays.
When the main screen is on: Tap its switch to toggle it On (blue) or off, then tap the setting to set what it will display. Checkmark any of the following items: Signature, Recent apps, App shortcuts, Music player, Quick contact, and /or Upcoming plans.
When the main screen is off: Tap its switch to toggle it On (blue) or off, then tap the setting to set what it will display. Choose Date & time or Signature. Tap the Settings icon to set the Signature style.