It is the only prayer attached to the Green Scapular. People are encouraged to give one to a non-catholic or fallen away catholic and ask them to say the prayer daily. If one cannot one is encouraged to carry it on their person, and say the prayer on behalf of the non-catholic or fallen away catholic. That is all that is required for this sacramental.
(Sacraments are instituted by Christ as a means of Grace)
Sacramentals are approved by the Church as a means of grace, but are not replacements for the seven Sacraments.