1. Go to 
Settings > 
Passwords & security > Screen lock.
2. Choose a screen lock type.
• Tap Pattern to draw a simple pattern with your finger to lock the phone.
• Tap Pin to enter 4 to 16 numbers to lock the phone.
• Tap Password to enter 4 or more letters or numbers to lock the phone.
Settings > Passwords & security > Screen lock.2. Choose a screen lock type.
• Tap Pattern to draw a simple pattern with your finger to lock the phone.
• Tap Pin to enter 4 to 16 numbers to lock the phone.
• Tap Password to enter 4 or more letters or numbers to lock the phone.