shave the head.

Numbers 6:5, 9
For the entire period of his vow of separation, no razor shall pass over his head. He must be holy until the time of his separation to the LORD is complete; he must let the hair of his head grow long. . . .

Acts 18:18
Paul remained in Corinth for quite some time before saying goodbye to the brothers. He had his head shaved in Cenchrea to keep a vow he had made, and then he sailed for Syria, accompanied by Priscilla and Aquila.

Acts 21:24, 26
Take these men, purify yourself along with them, and pay their expenses so they can have their heads shaved. Then everyone will know that there is no truth to these rumors about you, but that you also live in obedience to the Law. . . .

and put it

Luke 17:10
So you also, when you have done everything commanded of you, should say, 'We are unworthy servants; we have only done our duty.'"

Ephesians 1:6
to the praise of His glorious grace, which He has freely given us in the Beloved One.