At dawn or early in the morning before Yom Kippur, take a live chicken, fish or money which will then be given to charity and recite the following three times. Recite the first paragraph, pass it over your head three times and then recite the paragraph again, etc.

Children of man who sit in darkness and the shadow of death, bound in misery and chains of iron — He will bring them out of darkness and the shadow of death, and will sunder their bonds. Foolish sinners, afflicted because of their sinful ways and their wrongdoings; their soul loathes all food and they reach the gates of death — they cry out to the Lord in their distress; He saves them from their afflictions. He sends forth His word and heals them; He delivers them from their graves. Let them thank the Lord for His kindness, and [proclaim] His wonders to the children of man. If there be for a man [even] one interceding angel out of a thousand [accusers], to speak of his uprightness in his behalf, then He will be gracious to him and say: Redeem him from going down to the grave; I have found expiation [for him].

When reciting the first twelve words below, pass the chicken, fish or money over your head three times.
This is my exchange, this is my substitute, this is my expiation. This chicken shall go to death and I shall proceed to a good, long life and peace.
Click here for Hebrew and English text in printable PDF format (courtesy of Kehot Publication Society).
(by chabad.org)

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