Release the luggage strap clasp so that the strap is open.
Wrap the luggage strap completely around the width of your bag at its midpoint. This area tends to be the most vulnerable to failure as is has little framework and is furthest from the hinges or locking ends of the suitcase. The strap should pass through the side handle on its way around the bag. Keep the clasp facing toward the front of the bag for easy access.
Adjust the luggage strap to the appropriate size for your suitcase without locking it shut. Slide the floating adjuster toward the strap clasp and pull the strap away from it until the strap reaches the length you need. The fit should be snug and not allow for any movement.
Clasp the two ends of the luggage strap together securely.