To add your finger print on your Lenovo K4 Note you have to follow these steps:
1. Once you switch on your phone, you will have a list of icons, wherein there would be a "Finger print" icon.
2. As an alternative you can also go to the "Settings" to get this Option.
3. Click on the "Add Finger Print" Option.
4. There is a hollow place to put your finger at the back side of your phone just below the camera.
5. Keep placing your finger repeatedly till it shows it has scanned it 100%.
6. Once it is over, you can keep adding fingerprints of 5 fingers or even fingers of your family members too, if you want them to access your phone.
But before you go for adding the finger prints you need to set a 4 digit PIN to unlock your phone.