Can you outline the specific actions Baba performed just before leaving the Masjid for the Chavadi?

Certainly. Just before the procession began, Sai Baba followed a distinct ritual. According to Chapter 37, after Tatya Patil had placed a golden-bordered shawl over Him, Baba would first go to a wall where firewood was kept. He would move His right big toe at that spot for a moment. Following this, He would personally wave His right hand over the burning flame in the dhuni, extinguishing it. Only after these specific actions were completed would Sai set out for the Chavadi, signaling the start of the music and festivities.