Ex for registering.
FINGERPRINT 1: Swipe Thumb 2 times, Swipe Index Finger 2 times, Middle Finger 2 times, Ring Finger 2 times. (Not fully sure if you need to have it swiped 2 times or if 1 will work as well, 2 has seemed to work without flaws) Now you have 1 Print registered but in reality 4 have been registered.
Another quick tip is that you can swipe your thumb sideways, or at just the right angle, on the scanner so you can now unlock your phone with one hand. This is a bit tricky since you have to swipe your thumb in just the right spot.
Sent from my SM-G900P using XDA Free mobile app