Samsung Galaxy A3 (2016)
Android 5.1.1
1 Find "Screen lock type"
Slide your finger downwards starting from the top of the screen.
Press the settings icon.
Press Lock screen and security.
Press Screen lock type.
2 Create phone lock code
Press Pattern.
Slide your finger across the screen to connect at least four points and press CONTINUE.
Repeat the selected phone lock code and press CONFIRM.
3 Select PIN
Key in a four-digit PIN and press CONTINUE.
Key in the PIN again and press OK.
Press the required setting.
Press DONE.
4 Turn off use of phone lock code
Press Screen lock type and key in the current phone lock code.
Press None.
5 Return to the home screen
Press the Home key to return to the home screen.