It is customary to cover the Shofaros prior to saying the blessings. [Some write that the mouth of the Shofar however remains revealed. The Chabad Rebbe’s had a special order with regards to the coverings used.] The Shofar remains covered until after the blessings have been completed. One is to hold [with his right hand] the covered Shofar while the blessings are recited. [Some write that the Shofar is to remain covered throughout the time that it is not being blown after Tekios Meyushav, such as the intervals of before and during Musaf.]
How many Shofros is one to have available for the blessing?
It is accustomed to set up many Shofros at the time of the blessing, and have them all in mind during the blessing, just in case he needs to switch Shofros during the blows. The Rebbe Rashab had three Shofros set up, one being of the Maharal of Prague. Likewise the Rebbe had three Shofros, one black and two white. There was a special “Seder” in the setup of the Shofros before the Mitzvah.
 Elya Raba 585/8 in name of Hagahos Maimanis; Kitzur Shlah R”H; Beir Heiytiv 593 [end]; Derech Hachaim 3; M”E 585/3; Ben Ish Chaiy Netzavim 15; Avnei Nezer 431; M”E 585/3; Minchas Elazar 4/36; Kaf Hachaim 585/4; Sdei Chemed R”H 2/14; Otzer Minhagei Chabad 244
 The reason: Some write the reason for this is because the blessing recited is “on hearing the Shofar” and not on blowing it, and thus in order to hide its shame we cover it similar to the covering of the bread by Kiddush. [Avnei Nezer ibid; However see Minchas Elazar ibid] Alternatively the Shofar blowing is done to remind Hashem of Akeidas Yitzchak, and just like Yitzchak was hidden by Avraham while building the altar [as it says in the Midrash] so too we hide the Shofar. [Hagaon Radal brought in Alef Hamagen 585/7; Minchas Elazar ibid] Alternatively it is done in order so the Satan does not receive any nurture from the Shofar. [Likkutei Mahrich 70]
 Otzer Minhagei Chabad 244
 See Otzer Minhagei Chabad p. 114 that the Rebbe Rashab used two white kerchiefs and one red kerchief. Two were placed under the Shofar and one on top. Likewise the Rebbe had a special order followed in the covering of the Shofar with the kerchiefs.
 M”E ibid
 Siddur Yaavetz; Ben Ish Chaiy Netzavim 15; Kaf Hachaim 585/14; Alef Hamagen 585/7; Admur 206/8 [regarding holding the object of the Mitzvah with ones right hand]
The reason: As one must hold onto the object of the Mitzvah prior to saying its blessing. [Kaf Hachaim ibid based on 206/4; Admur ibid]
How is one to hold onto the Shofar while it is covered? One is to hold the Shofar within his right hand while it is covered. [Kaf Hachaim ibid; Alef Hamagen ibid] Some however write the custom is to place one’s hand into the cover and hold it. [Piskeiy Teshuvos 585/4] The Rebbe’s custom was to simply rest his hand on the cover of the Shofros. [Otzer Minhagei Chabad p. 115]
 Kaf Hachaim based on Kitzur Shlah ibid; Piskeiy Teshuvos 585/4
 Alef Hamagen 585/6; Piskeiy Teshuvos 585/6; See next Halacha in E in Q&A for the full discussion on this matter
 See Otzer Minhagei Chabad p. 113-114