BLUE GARUDA: i didnt knew that about the Heart Sutra, thanks (by the way, why do demons answer with 3 claps??)
You perform the 3 claps at the end of the sutra. There are 4, but I was taught that the last 3 act as instruction for the spirits to obey:
''Great Mother, Prajnaparamita, and all the Buddhas ans Bodhisattvas of the ten directions, through the power of your blessings may these true words of mine be achieved. Just as before, when by contemplating the profound meaning of the perfection of wisdom and reciting its words, Indra overcame all the harm of maras, non-humans and so forth, in the same way, by my contemplating the profound meaning of the perfection of wisdom and reciting its words:
May all the harm of maras, non-humans and so forth be overcome.(clap)
May they become non-existent. (clap)
May they be pacified.(clap)
May they be thoroughly pacified.(clap)''