Here are some steps to set-up your Android lock-screen password:
1. Browse through the 'Settings" of your Android smartphone.
2. Look for the "Security" tab and tap that tab.
3. Choose "Screen Lock" after that, choose "Password".
4. Input your desired password. (REMEMBER: Do not forget your password. Better write it in notebook.) Then tap "Continue". On the next prompt, you need to confirm your password so, just input/type the SAME password.
5. Then tap "OK". You have now a password lock-screen.