We remove the curtain from before the Holy Ark prior to the Ma’ariv service, as it says, The Lord has done what He planned; He has fulfilled His word (Eichah 2:17), which Chazal interpret to mean that HaShem, as it were, tore His garment. By doing this, we demonstrate how low we have descended since the Temple was destroyed (Rama 559:2). We return the curtain to its proper place before praying Minchah (K.H.C. 19).
Many also have a custom not to wear their prayer shawls (talit gadol) or don their tefillin during Shacharit prayers. Just as HaKadosh Baruch Hu, as it were, “fulfilled His word” – i.e., tore His garment – so too, we refrain from wearing a talit. And just as the verse states, He cast down from heaven to earth the glory of Israel (Eichah 2:1), which refers to God’s tefillin, so too, we refrain from adorning ourselves with tefillin. However, since most Rishonim hold that the mitzvah of donning tefillin takes affect on Tish’a B’Av as it does on all other days, we wear talit and tefillin at Minchah time. [The Rabbis] chose to abstain from these mitzvot during Shacharit because that is when we demonstrate the height of our mourning and pain through the recitation of Kinot. By Minchah time, in contrast, we already accept some consolation. The Shulchan Aruch codifies [this practice] into law (555:1), and all Ashkenazi communities, as well as many Sefardic ones, follow it. One should wear his talit kattan [the small four-cornered garment usually worn under one’s shirt] from the beginning of the day [as usual], but it is uncertain whether a blessing is said when putting it on. Therefore, it is preferable to sleep in one’s talit kattan on the night of Tish’a B’Av; this way, one will not have to recite the blessing in the morning. Only before Minchah will one recite the blessing, upon enwrapping himself in his large talit (prayer shawl).
There are some meticulous Jews who do not want to read the Shema without wearing a talit and tefillin. Therefore, they put them on at home, before Shacharit, read the Shema, and then go to pray with the congregation, without talit and tefillin. Some Sefardic communities wear talit and tefillin during Shacharit, [as usual]. Each community should continue observing its custom.