Does "pouring water on the person afflicted by the evil eye from behind their back" mean that another person should pour it, or that the afflicted person should do it themselves?

The person who cast the evil eye is commanded to perform ablution (wudu') and wash the inside of his lower garment (izar). Then, the water from this washing is poured over the person affected by the evil eye. The water is poured over his head and back from behind him, and then the vessel is overturned behind him. Another person can also pour the water over the person affected by the evil eye.