We ask forgiveness from others in preparation for Yom Kippur.
Some have the tradition of immersing in a Mikveh in preparation for Yom Kippur.
Omit Psalm 100 (MT 104)
When reciting every Kaddish, after the word "l'eilah," we add "u'l'eilah."
When reciting the Amidah, include passages marked, "Between Rosh Hashanah and Yom Kippur".
Conclude the service with Achat Sha'alti (MT 662).
Light candles before sunset. Recite the candle blessing for Yom Kippur and Shehecheyanu.
We wear tallot for the Kol Nidre service.
It is customary to wear white for all Yom Kippur services. Some wear a kittel.
We recite an abbreviated Kabbalat Shabbat, consisting of Psalms 92 and 93. Some congregations also recite a shortened form of L'cha Dodi before Psalm 92.
Include other changes for Shabbat as marked in the machzor.
In the afternoon, before Yom Kippur begins, it is a Mitzvah to eat a S'udah Mafseket. This should be a festive and satisfying meal, beginning with Hamotzi and concluding with a weekday Birkat Hamazon. We finish the meal before sundown, and we light our candles. This meal is not only in preparation for the fast to follow, but also to express our hopes that our Yom Kippur observance will lead us to a good new year (JL 123). Our tradition teaches us that, just as it is a Mitzvah to fast on Yom Kippur, it is also a Mitzvah to eat the day before Yom Kippur. It should be a festive meal, as Erev Yom Kippur is considered a partially festive day: we express our confidence that God with treat us mercifully this Yom Kippur.
During the Aseret Y'mei T'shuvah (10 days of repentance from Rosh Hashanah through Yom Kippur):
Traditionally, congregations continue reciting S'lichot each morning before shacharit. When reciting every Kaddish, the words "l'eilah min kol," are changed to "l'eilah u'l'eilah mi-kol."
When reciting the Amidah, include passages marked "Between Rosh Hashanah and Yom Kippur."
We continue to conclude our Shacharit and Ma'ariv services with Achat Sha'alti (MT 662).