When stepping on the platform to activate the elevator you slightly step of the edge of the platform and face away from the wall. Jumping will put Mos partly into the wall and rapidly lift her to the top. If you jump and hit the wall you are too far over the edge. Otherwise you might need to step a pixel back to perform the lift.
It takes some practice to perform this trick reliably but using this glitch you are able to save about 5 seconds overall time when going for a Speedrun record.