At the end of each handle, there's a lock. Unlock it by pulling the lock downward while holding the tip of the rope, then adjust the rope, lock it back when done.
Do the same to the other side's lock.
Make a figure of 8 knot on each side of the rope. (check the video link below for the tutorial)
The knots will add weight to each side of the rope so that you can feel where the rope is during the revolution.
Last thing, check if the rope length is already at least chest level.