It is customary to perform the kaparot (symbolic "atonement") rite in preparation for Yom Kippur.
The rite consists of taking a chicken and waving it over one's head three times while reciting the appropriate text. The fowl is then slaughtered in accordance with halachic procedure and its monetary worth given to the poor, or, as is more popular today, the chicken itself is donated to a charitable cause.
We ask of G-d that if we were destined to be the recipients of harsh decrees in the new year, may they be transferred to this chicken in the merit of this mitzvah of charity.
In most Jewish communities, kaparot is an organized event at a designated location. Live chickens are made available for purchase, ritual slaughterers are present, and the slaughtered birds are donated to a charitable organization. Speak to your rabbi to find out whether and where kaparot is being organized in your area.
Kaparot can be done any time during the Ten Days of Repentance (i.e. between Rosh Hashanah and Yom Kippur), but the ideal time is on the day preceding Yom Kippur during the early pre-dawn hours, for a "thread of Divine kindness" prevails during those hours.
Several reasons have been suggested for the choice of a chicken to perform the kaparot rite: 1) In Aramaic, a rooster is known as a gever. In Hebrew, a gever is a man. Thus we take a gever to atone for a gever. 2) A chicken is a commonly found fowl and relatively inexpensive. 3) It is not a species that was eligible for offering as a sacrifice in the Holy Temple. This precludes the possibility that someone should erroneously conclude that the kaparot is a sacrifice.
It is customary to use a white chicken, to recall the verse (Isaiah 1:18), "If your sins prove to be like crimson, they will become white as snow." In any event, one should not use a black chicken, as black is the color that represents divine severity and discipline. Nor should one use an obviously blemished chicken.
A male takes a rooster; a female uses a hen. Ideally every individual should use their own chicken. If, however, this is cost prohibitive, one fowl can be used for several individuals. So an entire family can do kaparot with two chickens—one rooster for all the males and one hen for all the females.
A pregnant woman should perform kaparot with three chickens—two hens and a rooster. One hen for herself, and the other hen and rooster for the unborn child (of undetermined gender). Or, if this is too expensive, one hen and one rooster will suffice (and if the fetus is female, she shares the hen with her mother).
If a chicken is unavailable, one may substitute another kosher fowl (besides for doves and pigeons, as they were offered as sacrifices in the Holy Temple). Some use a kosher live fish; others perform the entire rite with money, and then giving the money – at least the value of a chicken – to charity.
Click on "blessing" for the Hebrew and English text of the kaparot.
Take the chicken in your hands and say the first paragraph ("Children of man who sit in darkness...")
When reciting the beginning of the second paragraph, wave the chicken over your head in circular motions three times—once when saying, "This is my exchange," again when saying "This is my substitute," and again when saying, "This is my expiation."
Repeat the entire process another two times. (Altogether waving the chicken over your head nine times.)
Rest both your hands on the bird—as was customarily done when bringing a sacrifice in the Holy Temple.
Take the chicken to the shochet (ritual slaughterer), who slaughters the bird.
Here's your chance to fulfill a relatively rare biblical mitzvah—that of covering the blood of a slaughtered bird. Take a handful of dirt (usually made available in the area) and recite the following blessing before covering the blood: Baruch attah Adonai Eloheinu melech haolam, asher kidishanu b'mitzvotav v'tzivanu al kisui hadam be'afar. (Blessed are You, L‑rd our G‑d, King of the universe, who has sanctified us with His commandments and commanded us concerning covering the blood with earth).
It is customary in many communities to tip the shochet for his service.
If you're reluctant to hold a live chicken in your hands, someone else can hold the chicken and wave it over your head.
Even the smallest of children are traditionally brought to kaparot, and one of their parents waves the chicken over the child's head, while saying, "This is your exchange, this is your substitute, this is your expiation..."
It is of utmost importance to treat the chickens humanely, and not to, G‑d forbid, cause them any pain or discomfort. Jewish law very clearly forbids causing any unnecessary pain to any of G‑d's creations. The repugnance of such an unkind act would certainly be amplified on this day, the eve of the day when we beseech G‑d for – perhaps undeserved – kindness and mercy. In fact, the Code of Jewish Law suggest that we take the innards and liver of the kaparot chickens and place them in an area where birds can feed off them. "It is proper to show mercy to the creatures on this day, so that in Heaven they should have mercy upon us [too]."
The same procedure outlined above is followed – sans the ritual slaughterer – if using fish or money for kaparot.