Based on the teachings cited in the Shri Sai Satcharita, how exactly should a devotee serve a Guru to gain true knowledge?

The preface in Chapter 0 draws upon the wisdom of Dnyaneshwar Maharaj to outline the method of proper service. It is not merely a physical act but a complete surrender of one's body, mind, and soul at the Guru's feet. A crucial element is to perform all service entirely without ego. As the verses from Shri Dnyaneshwari explain, service is the very doorway to the treasure of knowledge. By making this selfless service your own, the Guru will then impart the wisdom that enlightens the heart and ensures that doubts will not arise.