What is described as the most certain and effective method of Guru service for attaining salvation?

According to the guidance provided in Chapter 0, the best and most certain service for achieving the fruit of salvation is to write the biography of one's own Sadguru. This should be undertaken with a pure heart, firm resolve, excellent faith, selfless love, and unwavering devotion. This practice involves not just writing but also personally studying the text regularly, performing hundreds of readings known as Parayans, and conducting weekly recitations called Saptahs. It is noted that this profound form of bodily and verbal service does not conflict with maintaining one's family or worldly responsibilities.