Use Touch ID
You can set your phone to use your fingerprint as phone lock code or to authorise iTunes and App Store purchases. To use Touch ID, you need to turn on the phone lock code.
Press Settings.
Press Touch ID & Passcode.
Press Add a Fingerprint....
Follow the instructions on the screen to add your fingerprint.
Press Continue.
Press Continue.
Press the indicators next to the required settings to turn them on or off.
Press the Home key to return to the home screen.
1. 1. Find "Touch ID & Passcode"
2. 2. Add fingerprint
3. 3. Select Touch ID settings
4. 4. Return to the home screen