Kaushitakagrihyasutra 1.21: atha ekaviṃśaḥ khaṇḍaḥ

In the first year is the tonsure of a brāhmaṇa;

or in the third year.

In the fifth [year] of a kṣatriya;

in the seventh of a vaiśya;

or in the first year for all.

Having set up the fire, having filled bowls of rice and barley, and of sesame and black beans, he places to the north bull's dung, a mat of kuśa grass for receiving the hair, a mirror, an iron razor, and fresh butter.

He pours cold water into warm water with [the verse]: 'Mix together, O regular waters, wavy, sweetest, mingling with sweet milk, delightful for the attainment of wealth.'

With the cold and warm waters he moistens the right hair-side three times with: 'May the waters moisten [you] for life, for longevity, for luster. The triple-life of Jamadagni, the triple-life of Kaśyapa, the triple-life of Agastya, whatever triple-life belongs to the gods, may that triple-life be yours.'

In the very same way, having smeared it with fresh butter,

he inserts a young kuśa shoot with, 'O herb, protect him!'

Having touched the hair and the young kuśa shoot with the mirror, he takes the iron razor with, 'You are vigor; the axe is your father; do not harm him!'

With, 'With which razor Savitṛ shaved the head of King Soma and Varuṇa, knowing, with which the Creator shaved the head of Bṛhaspati and of Indra, with that, O brahmins, shave this [head] of his; may this hero [so-and-so] be long-lived, endowed with life,' he cuts the ends of the hair and the young kuśa shoot.

A second time in the same way.

A third time in the same way.

In the same way twice on the north side.

At the armpits [occur] the sixth and seventh [cuttings] in the rite of shaving the beard.

This rite of shaving the beard is the same as the tonsure, in the sixteenth or eighteenth year.

At the third shaving, however, he gives a cow,

and the unwashed garment covered with which he shaves.

The rites for girls are performed silently.

They bury the hair in the north-eastern direction, or near water, in a place covered with plants.

To the barber belong the bowls of grain; to the barber belong the bowls of grain.

Thus ends the first chapter in the Kauṣītaka Gṛhyasūtra.