With the activity tracker resting on your wrist (holes side of the wristband on the pinky finger side of your hand and clasp side on the thumb side of your hand), push the "holes" end of the wristband against your wrist, while using your index and thumb to pinch the clasp end of the wristband and pull it over the holes end. Keep the two ends of the wristband pressed against your wrist using your thumb, while moving your index finger behind the desired position you wish to fasten the clasp into. Pinch the wristband closed.

Tip: You may find it helpful to add a few drops of water to the holes of the wristband to make closing it easier.