Jodorowsky's Dune Uncovered
Scene 106-108 : Worm Ride
The Fremen lead Paul and Jessica to the edge of the desert, and a thumper is planted. Stilgar ties Jessica to him and warns her not to make a mistake as their lives depend on it.
In the distance a worm can be seen approaching, and the Fremen chant as it draws near.
While the worm is attracted to the thumper Stilgar, and by necessity Jessica rush towards it, followed by the other Fremen.
Stilgar uses hooks to attach to the worm, as do the other Fremen, and the worm turns lifting them onto its back.
The worm then carries them across the desert towards some rocky hills - Sietch Tabr, a large oasis in the middle of the desert.
In the Moebius storyboards we see Stilgar using an electric prod on the sandworm, a device that isn't mentioned in the script.