You can Enable Pattern Lock from Phone Settings option.
2. PIN Lock
PIN Lock is second choice for any android users after pattern lock. Pin Lock is secured and harder to guess comparing pattern lock. Pin Lock is also remind me iPhone. Using Pin Lock is secure your android phone from guessers who try to unlock you android phone. Always Choose Harder PIN for your android phone. Make your Phone PIN Lock Look like iPhone from iOS Lockscreen App.
Pin Lock
3. Password
You can say this is most secure way for locking your android phone . This is harder to guesses , no one know what is your android mobile password. PIN and Pattern Lock is not so much secure like Password Lock. If you really want secure your android phone use password Lock in your android phone.
Password Lock
4. Lock Your Android Phone from Device Manager
If somehow you lost your android phone, you can also lock your android phone from device manager website.
Invisible Pattern Lock is one of the most amazing pattern lock , only you know the pattern and only you can unlock your android phone. Download Knock Lock app and set your pattern , just press your pattern password and you can unlock your android phone.
Personally I don’t recommend you to download and set Fingerprint and Facelock in your android phone. These apps are not correctly work in every android phone. Just Ignore these type of android apps from installing in your android phone.