Shabbos Chol Hamoed:
Cutting nails Erev Shabbos Chol Hamoed: If one cut his nails on Erev Yom Tov then the following is the law: One who cut his nails on Erev Yom Tov [or in close proximity to Erev Yom Tov to the point there was nothing to cut before Yom Tov] is permitted to cut his nails during Chol Hamoed. If one did not cut them Erev Yom Tov then the following is the law: Some Poskim rule it is forbidden to cut nails on Erev Shabbos, or Erev Yom Tov of the last days, if he did not cut them on Erev Yom Tov of the first days. Other Poskim, however, rule it is permitted to cut nails on Erev Shabbos [or Erev Yom Tov] if one is accustomed to do so on every Erev Shabbos throughout the year. It is implied from Admur like the former opinion, that it is forbidden to cut them. According to all it is forbidden to cut the nails on Erev Shabbos if he is not accustomed to always do so.
Read Haftorah of Shabbos Chol Hamoed on Erev Shabbos: On Shabbos Chol Hamoed Sukkos and Pesach one is to read to himself both the Haftorah of the Parsha of the coming week and the Haftorah which is read that Shabbos.
Shabbos candles-Where are the candles to be lit: The candles are to be lit within the Sukkah. If this is not possible [such as due to safety reasons] then one is to light inside.
Hodu before Mincha of Erev Shabbos: Hodu is omitted prior to Mincha Erev Shabbos which is also Yom Tov or Chol Hamoed. Patach Eliyahu is recited even when Hodu is omitted such as Erev Shabbos Chol Hamoed.
Kabalas Shabbos: On Shabbos Chol Hamoed one begins the Maariv prayer from Mizmor Ledavid [psalm 29], [omitting all the Psalms from Lechu Neranina until Mizmor Ledavid]. [One recites the entire Nusach from Mizmor Ledavid and onwards, including Ana Bekoach; all the stanzas of Lecha Dodi; Mizmor Shir, Kegavna. In Lecha Dodi, the wording of Besimcha instead of Berina is recited.
Shemoneh Esrei: The Shabbos Chol Hamoed Shemoneh Esrei for Maariv, Shaacharis and Mincha follows the same Nusach of prayer as a regular Shabbos, with exception to that Yaaleh Veyavo is added in the Shemoneh Esrei.
Kiddush: On Shabbos Chol Hamoed the following passages prior to Kiddush are read in an undertone: shalom aleichim, eishes chayil, mizmor ledavid Hashem ro’i, da hi se’udasa. The blessing of Leishev Basukkah is said by Kiddush of both night and day, as explained in Chapter 3 Halacha 11B, see there.
Hoshanos: Hoshanos is not recited on Shabbos Chol Hamoed, as explained in Chapter 11 Halacha 13. [However, on Sunday, one recites the Hoshanos of that day, and the skipped Hoshanos of Shabbos, with saying the Hoshanos of Shabbos first. Nonetheless, we only encircle the Bimah once by that days Hoshanos. Seemingly, this applies even when Hoshanah Raba falls on Sunday.]
Musaf: For Musaf one prays the same Nusach prayed by Musaf of Yom Tov, although reciting the Shabbos additions. If one forgot to mention the Shabbos sacrifices in Musaf then if one said “Kimo Shekasuv Besorasecha” he has fulfilled his obligation. The same applies whenever one forgets to mention a particular Karban. [If one Davened Musaf of Shabbos instead of Yom Tov, then he does not fulfil his obligation.]
Kerias Hatorah: Two Sifrei Torah are removed from the Ark. In the first Sefer Torah one reads the Parsha of “Rei Ata Omer Eilay.” In the second Sefer Torah one reads the Maftir from Pinchas, discussing that days sacrifice.
Haftorah: Both the Haftorah of Shabbos Chol Hamoed Pesach and Sukkos discuss the times of the redemption. On Pesach the Haftorah discusses the resurrection, being that the resurrection will take place in Nissan. On Sukkos the Haftorah discusses the battle of Gog and Magog, being that in Tishrei there will be the war of Gog and Magog. Thus, the Haftorah is read from the portion of “Vehaya Bayom Bo Gog” found in Yechezkal. The last blessing said after the Haftorah on Pesach concludes with only “Mikadesh Hashabbos” being that Chol Hamoed Pesach is not considered a separate Yom Tov. On Sukkos, however, it ends with “Mikadesh Hashabbos Yisrael Vehazmanim” being that each day is a separate Yom Tov.
Havdalah: One recites Havdalah as usual for Motzei Shabbos, on Motzei Shabbos Chol Hamoed. [Havdalah is to be recited in the Sukkah as explained in Chapter 3 Halacha 6E, with a blessing of Leisheiv Basukkah, as explained in Chapter 3 Halacha 11E.]
Is Vayiten Lecha recited on Motzei Shabbos Chol Hamoed?
 M”A 532:1; Chayeh Adam 109:3; M”B 532:2; Kitzur SH”A 104:12; Chol Hamoed Kehilchasa 4:5; Kaf Hachaim 532:7
Other Opinions: The Elya Raba 532:1 rules one may only remove the nails with a knife and not with scissors.
 Aruch Hashulchan 532:2
 The reason: The reason for this allowance is because even regarding a haircut there are Poskim who allow it to be done on Chol Hamoed if one cut his hair on Erev Yom Tov. Thus, regarding cutting nails, which is itself disputed whether it is at all forbidden during Chol Hamoed, one may certainly be lenient if he cut his nails on Erev Yom Tov. [M”A 532:1; P”M 532 A”A 1]
 See Shaareiy Teshuvah 468:1; Kaf Hachaim 532:5
 Shvus Yaakov 1:17, brought in Shaareiy Teshuvah 468:1; Koveitz Mibeis Levi 1:47 that so is the custom; Piskeiy Teshuvos 532:1
 Nachalas Shiva 2:57, brought in Beir Heiytiv 532; Shulchan Gavoa 532:2; Chol Hamoed Kihilchasa 4:6; Kaf Hachaim 532:5 concludes one who is lenient has upon whom to rely; Aruch Hashulchan 532:2 rules that if one did not cut the nails on Erev Yom Tov due to reasons that were beyond his control, then he may cut it during Chol Hamoed.
 Chol Hamoed Kihilchasa 4:6
 As it is permitted to cut nails for the sake of a Mitzvah and cutting them on Erev Shabbos in honor of Shabbos is a Mitzvah. [ibid]
 So is implied from Admur 468:6 from the fact he forbids cutting the nails on Erev Pesach past Chatzos even though it is Erev Yom Tov. See Shvus Yaakov ibid. It is thus a wonderment that Chol Hamoed Kihilchasa 4:6 rules plainly that it is allowed despite this clear ruling of Admur.
 Hisvadyus 1985 Vol. 1 p. 351
 Admur 639:3 “A candelabra at the time that is lit needs to be inside the Sukkah”; Michaber 639:1; Sukkah 29a
 As it is belittling of Yom Tov to recite a thanks to Hashem for removing us from the mundane activity of the week to Shabbos when Yom Tov is likewise not a time of mundane activity. [Ketzos Hashulchan 77 footnote 2]
 Ketzos Hashulchan 77 footnote 3
 Siddur Admur regarding Yom Tov; Ketzos Hashulchan 77:2; Shaar Hakolel 17:6 states that this was mistakenly omitted from certain prints of the Siddur
Other customs: Some are accustomed to beginning Maariv from after Lecha Dodi, by Mizmor Shir. [M”E 625:41]
 The reason: Some write the reason is because there is a Mitzvah of Simcha on Yom Tov and we hence desire to speed the conclusion of Maariv. [Otzer Minhagei Yeshurun p. 64; See Admur 270:1 regarding Bameh Madlikin that it is omitted on Yom Tov in order to hasten Simchas Yom Tov] Alternatively the reason is because these Psalms contain the words Rina, and on Yom Tov we emphasize the words Simcha. [Ketzos Hashulchan 77 footnote 13] Alternatively, the reason is because the first five Mizmorim until Mizmor Ledavid relate to the five weekdays until Erev Shabbos while the psalm of Mizmor Ledavid relates to Erev Shabbos. Hence, we omit the first five Zemiros as it is not proper to relate them to Yom Tov. [Sichas Kodesh 2 p. 121]
 Shaar Hakolel 17:6; Ketzos Hashulchan 77 footnote 13; Otzer Minhagei Chabad p. 63
Other customs: Some are accustomed to only recite the first and last stanza of Lecha Dodi. [M”E 625:41] Others recite the first two stanzas of Lecha Dodi corresponding to Zachar and Shamor. [Alef Hamagen 625:56] Others recite the entire Lecha Dodi with exception to the stanza of Hisnaari Meiafar Kumi which is omitted. [Peri Megadim] Some are accustomed to omit Kegavna being that it mentions that all the other days are filled with wrath which is untrue regarding Yom Tov. [Siddur Yaavetz; Likkutei Mahrich Pesach; Alef Lamateh 625:67; Divrei Torah 9:72; Piskeiy Teshuvos 487:3]
 Hagahos Hasiddur of Rebbe Rashab; Ketzos Hashulchan 77:2; Mishnes Chassidim “Leil Yom Tov” 1:2].
Difference between Rina and Simcha: The term Rina denotes a bittersweet joy, a joy that comes as a result of a previous distance. However, Simcha does not have any bitterness mixed with it at all. [Magen Avos Vayishlach’ Ketzos Hashulchan 77 footnote 13]
 Michaber 663:2; See Admur 490:15 regarding Pesach
 Sefer Haminhagim p. 118 [English] regarding Rosh Hashanah; See Otzer Minhagei Chabad Nissan p. 142; See Mateh Efraim and Alef Hamagen 583:1
Original Chabad custom: In the earlier prints of Hayom Yom p. 46 it stated that one does not say Shalom Aleichem or Eishes Chayil at all on Shabbos Yom Tov or Shabbos Chol Hamoed. This was based on an explicit directive of the Rebbe Rayatz that one is not to say it and that so was the custom of the Rebbe Rashab and the Rebbe Maharash, although there were some years in which they said it. [Reshimos 4:12 and 22]
 Piskei Dinim Tzemach Tzedek end of Orach Chaim 660; Shaar Hakolel 45:3; Hayom Yom 17th-18th Tishrei; Sefer Haminhagim p. 67
 Hiskashrus that so was testified of Rebbe, that he was seen to say something prior to the start of the Hakafops by Hoshanah Raba of such a year
 Michaber 663:2; See Piskeiy Teshuvos 663:2 regarding cases of mistake
 Shaareiy Teshuvah 490:3; Piskeiy Teshuvos 663:2
 Michaber 663:3
 Admur 490:16
 Michaber 663:3
 Admur ibid; M”A 663:2; Sefer Haminhagim p. 68; See Shaar Hakolel 25:4; Otzer Minhagei Chabad p. 328
 Rama 663:2; Piskeiy Teshuvos 663:2
 M”A 663:1
 Otzer Minhagei Chabad p. 329 as is evident from the fact that it is omitted by Admur in the Siddur.
 P”M 295 M”Z 3; Beir Heiytiv 491:1
 Elya Raba 491:2; Aruch Hashulchan 295:3 His reasoning is because Chol Hamoed is forbidden in Melacha, and it is hence a belittling of Chol Hamoed to bless the weeks Melacha.
 Hayom Yom 19th Nissan