Only by Guru's Grace
We should especially know that service to Krsna with mamata (a sense of “mineness” towards Lord Krsna) is uttama-bhakti, and the increase of mamata in service, places a devotee in successively higher stages...
Why Not Only One Book?
Not everyone is in the same stage of bhakti. Everyone is in different stages. If one is a neophyte and does not have even sraddha, how can you tell him, “You are a manjari; book your ticket for only the manjari mood”? I want to tell you all, that this is a very wrong idea. Try to truly understand and then follow the real meaning of rupanuga...