It is customary to recite verses of scripture when opening the ark, when the Torah is escorted to the bimah (pulpit), and when it is brought back to the ark, as printed in the siddurim – each ethnic group according to its custom.
Ashkenazim are accustomed to first say “El Erech Apayim…” which is not recited on days that there is no Tachanun, and after several verses they recite “Berich Shemei.” Sephardim are only accustomed to recite “Berich Shemei” on Shabbat and Festivals, though some say it on Rosh Chodesh as well (Piskei Teshuvot 134:13).
The chazan holds the Torah scroll with his right hand, and when he says “Gadlu” he raises it a little. On Shabbat and Festivals he elevates it slightly when he says “Shema” and “Echad” as well. After that, he walks to his right to take the Torah to the bimah where it is read (Rama 134:2; Mishnah Berurah 13). It is customary that people kiss the Torah as it passes and partially escort it on its way. Most people are accustomed to kiss the Torah directly with their lips, yet some touch it with their hand and then kiss their hand (see Piskei Teshuvot 149:1-2). It is not proper for a person who is sick, or has a cold, to kiss the Torah directly with his mouth, so as not to infect the other people praying.
Before the reading, it is the task of the gabbai to prepare the Torah scroll at the proper place so that it will not have to be rolled there in public, because it is disrespectful to compel the congregation to wait. Generally there is no need to prepare the scroll, since the reading is conducted according to the order of the weekly Torah portions, and thus the Torah is opened to the place where the previous reading left off. However, on Festivals, Rosh Chodesh, and fast days, the Torah is read out of its usual order, and it is necessary to prepare the Torah scroll ahead of time. Afterwards, it must be rolled back to the order of the weekly Torah portion.
If, by mistake, a different Torah scroll was taken out, the prevalent custom is not to switch it. Even though the congregation will have to wait until it is rolled to the place of the reading, nevertheless, that is part of the honor shown to the Torah scroll; once it is removed from the ark, it is not replaced by another (Kaf HaChaim 144:13). Some say, in order not to waste the congregation’s time, it is permitted to switch a Torah scroll which was removed mistakenly, even if it was already placed onto the bimah. In times of need, when the congregation is strict about its time, we may rely on that opinion (Igrot Moshe, Orach Chaim, part 2, 37).