You can follow the link: https://youtu.be/u6tzvLj3CRE
PS: Press the locking button on the first tier, then slowly retract the first tier inwards, making sure you keep your fingers away from the folded area of the ladder. When the first tier is fully retracted, press the lock button on the second tier and then slowly but steadily retract the second tier inwards, taking care to ensure that your fingers and hand are clear of the folded area of the ladder.
By vevor