1. From the home screen, swipe down from the Notification bar.
   
2. Tap the Settings icon.
   
3. Under the 'General' tab, tap Accessibility.
   
4. Edit accessibility settings as desired.
   
5. To enable TalkBack, tap the TalkBack switch.
   
6. Tap Yes.
   
7. Double-press the Back key to exit the tutorial.
   
8. To disable TalkBack, tap to select the TalkBack switch.
   
9. Double-tap anywhere on the screen to flip the switch.
   
10. Tap to select Yes.
    
11. Double-tap anywhere on the screen to confirm the selection.