א אֵין לְדַבֵּר בֵּין תְּפִלָּה לִנְפִילַת אַפַּיִם. כְּשֶׁנּוֹפֵל עַל פָּנָיו, נָהֲגוּ לְהַטּוֹת עַל צַד שְׂמֹאל. הַגָּה: וְיֵשׁ אוֹמְרִים דְּיֵשׁ לְהַטּוֹת עַל צַד יָמִין, וְהָעִקָּר לְהַטּוֹת (רִיבַ"שׁ סי' רי"ב וּבֵית יוֹסֵף בְּשֵׁם הָרוֹקֵחַ) בְּשַׁחֲרִית כְּשֶׁיֵּשׁ לוֹ תְּפִלִּין בִּשְׂמֹאלוֹ, עַל צַד יָמִין מִשּׁוּם כְּבוֹד תְּפִלִּין; וּבְעַרְבִית, אוֹ כְּשֶׁאֵין לוֹ תְּפִלִּין בִּשְׂמֹאלוֹ, יִטֶּה עַל שְׂמֹאל (מִנְהָגִים). וּלְאַחַר שֶׁנָּפַל עַל פָּנָיו יַגְבִּיהַּ רֹאשׁוֹ וְיִתְחַנֵּן מְעַט מִיֹּשֶׁב, וְכָל מָקוֹם וּמָקוֹם לְפִי מִנְהָגוֹ; וּמִנְהָג פָּשׁוּט לוֹמַר: וַאֲנַחְנוּ לֹא נֵדַע כו' וַחֲצִי קַדִּישׁ אַשְׁרֵי לַמְנַצֵּחַ (טוּר), וַאֲפִלּוּ בְּיָמִים שֶׁאֵין אוֹמְרִים תַּחֲנוּן אוֹמְרִים לַמְנַצֵּחַ, מִלְּבַד בְּרֹאשׁ חֹדֶשׁ וַחֲנֻכָּה וּפוּרִים וְעֶרֶב פֶּסַח וְעֶרֶב יוֹם כִּפּוּר וְט"וּ [וט'] בְּאָב (מִנְהָגִים וְע"ל סי' תקנ"ט).
1 The Laws of "Nefilat Apayim" ("Falling on the Face"). Containing 8 S'ifim: One should not speak between [the Amidah] Prayer and N'filat Apayim. When one "falls on one's face", the custom is to lean [on] one's left side [i.e. arm]. Rema: And there are those who say that one should lean on one's right side [arm]. But the correct way (Rivash S'if 212; and Beit Yosef in the name of the Rokeach) is that during Shacharit when one has tefillin on one's left [arm], one should lean on one's right side [arm] because of honor for the tefillin. But [towards] the evening (i.e., when doing Nefilat Apayim during Mincha), or when one is not have tefillin on one's left, he should lean on one's left [arm]. (Minhagim [of the Maharil, etc.]) And after one "fell on his face", one should lift one's head and supplicate a little while sitting; each place should do according to their custom. And the widespread custom is to say "Va-anachnu lo neida..." ["And we do not know..."] and then Half Kaddish, Ashrei, and La-m'natzeyach (Tur). And even on days when we do not recite Tachanun, we say La-m'natzeyach, except for Rosh Chodesh, Chanuka, Purim, Erev Pesach, Erev Yom Kippur, and the 9th of Av. (Minhagim. And see below in siman 559)