934. Blowing Shofar after Yom Kippur
133:25 We should abolish the practice to have a non-Jew light candles for the piyyutim (liturgical poems) recited at Ne'ilah. He may, however, rearrange the existing candles so that they are better distributed throughout the shul. This is permitted as it is far enough removed from a prohibited activity (though the non-Jew should be contracted for this purpose in advance - Mishnah Brurah 623:3). (Editor's note: obviously, this halacha does not apply to those of us who now use electric lighting.)
133:26 After Ne'ilah, we recite Avinu Malkeinu, even if Yom Kippur was on Shabbos and it is still daytime. This is followed by Shema once, "Baruch Sheim..." three times and "Hashem Hu ha'Elokim" (Hashem: He is G-d) seven times, to accompany His "presence" as it departs. The shaliach tzibbur recites full kaddish in a joyful tune and we blow one shofar blast. (Some places have the custom to blow the shofar before kaddish - Rema 623:6.) This is the sign of G-d's "presence" departing, as at the giving of the Torah: "when the horn sounds a long blast" (Exodus 19:13). Also, Psalms 47:6 tells us, "G-d has gone up with a shout (teruah)." The practice to blow shofar also serves as a reminder of the shofar that was blown on Yom Kippur of the jubilee year. We may blow shofar even if the stars have not yet come out and it is still twilight, even when Yom Kippur falls on Shabbos. However, if it is still day, then we do not blow the shofar. After blowing shofar, everyone says "next year in Jerusalem" three times. (Mishnah Brurah 623:13 simply says that we say "next year in Jerusalem" but it doesn't say to do so three times.)