Yahrzeit is observed each year on the date of death according to the Hebrew calendar. Therefore, the timing of Yahrzeit on the secular calendar will vary from year to year.
The Yahrzeit observance lasts a full day and it is customary to attend services on the evening Yahrzeit begins as well as the morning and afternoon of the next day.
Those who come to observe Yahrzeit recite kaddish as part of the daily service.
It is traditional to make contributions to charity on Yahrzeit. Perhaps the best known custom for observing Yahrzeit is lighting a candle made to burn for at least 24 hours. The candle is lit the evening Yahrzeit begins. If Yahrzeit falls on Shabbat or Yom Tov, the candle is lit before the Shabbat or holiday candles. Although there is no formal blessing when lighting the candle, a meditation such as the one which follows may be said. It is appropriate, of course, to use your own words and thoughts in addition or in place of this meditation.
Dear God, I light this candle on this Yahrzeit of my dear _________. May I be inspired to deeds of charity and kindness to honor his/her memory. May the light of this candle be a reminder to me of the light my dear ________ brought to my life. May his/her soul be bound up in the bond of eternal life. Amen.