According to the provided text from Chapter 11, what methods did Sai Baba use to guide his devotees from the worship of his physical form to the realization of the formless?

As detailed in Chapter 11, Sai Baba employed a variety of methods to help his devotees realize the Nirguna, or formless aspect of the divine, based on their individual eligibility. The text mentions that he would sometimes keep them at a distance or even forbid them from seeing him for long periods. Other methods included sending a devotee to another country, confining another to solitude within Shirdi, locking someone in the Wada, or assigning them the task of reading scriptures. By practicing these disciplines over many years, the devotees' longing for the Nirguna would grow, and their minds would become constantly occupied with Baba's spiritual company.