In the process described up until now, it's likely that we've omitted something, done something in the wrong order, done something incorrectly, forgotten something, or gotten something messed up -- it's very complex. So, at this point, at the bottom of page 45, we have the recitation of the Hundred Syllable Mantra of Vajrasattva. (In the animated GIF below, the Mantra will play through all of the syllables in a little over a minute. The Sanskrit transliteration employed is slightly different from the Tibetan pronunciation, but the relative pacing is fairly close to one way of chanting the Mantra.)
The power of this Mantra is to correct all these errors, to fill in all of the omissions, and to straighten it all out so that we don't have to be concerned with errors or problems we have in the meditation.