It is forbidden to sew brand new garments during the Nine Days, starting from Rosh Hodesh Ab. Repairing garments, however, such as mending tears, sewing a patch or sewing a button that had fallen, is allowed. One should not purchase new garments or new shoes during the Nine Days. Before the Nine Days, starting from Shiba Asar Be'Tammuz, it is customary not to wear new garments, as we do not recite the Beracha of "She'hehiyanu" during this somber period, but one may purchase new garments to wear them after Tisha B'Ab. Starting from Rosh Hodesh Ab, however, one should not purchase new garments even if he does not intend to wear them until after Tisha B'Ab. This Halacha applies only to significant articles of clothing. Items such as hosiery, socks and undergarments, the purchase of which does not bring special joy, may be bought during the Nine Days. The Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909) writes that if a garment becomes available at a bargain price during the Nine Days, and the item will be more expensive after Tisha B'Ab, then one may purchase it during the Nine Days. Hacham Bension Abba Shaul (Israel, 1924-1998) ruled that if one's shoes were torn during the Nine Days, he may purchase a new pair. If a person realized before Tisha B'Ab that he does not have footwear for Tisha B'Ab – meaning, shoes or slippers that don't contain leather – then he may buy a pair of shoes to wear on Tisha B'Ab. He may wear them for the first time on Tisha B'Ab, because he wears them for the purpose of mourning, and this does not bring him special joy. If he has other shoes that are permissible for Tisha B'Ab, then he should preferably wear that other pair rather than purchase a new pair. But if he would otherwise need to go barefoot, he may certainly purchase a new pair of shoes. Regardless, Rav Yaakob Haim Sofer (Baghdad-Jerusalem, 1870-1939) writes in Kaf Ha'haim (551:96) that already before Rosh Hodesh Ab, one should make sure that he has suitable shoes for Tisha B'Ab. If somebody makes clothing for a living, he may continue working until the onset of the week of Tisha B'Ab, at which point he must refrain. However, if a tailor is very poor and needs to continue working so he can afford his basic necessities, then he may continue working even during the week of Tisha B'Ab, and, if necessary, even on Tisha B'Ab itself. If somebody owns a factory that manufactures clothing, and he would incur a loss by shutting the factory down during the Nine Days, as he would still be required to pay his employees, he may keep the business running. Even on Tisha B'Ab itself, a person is permitted to work when this is necessary to avoid a substantial financial loss, and so certainly during the Nine Days, one may continue manufacturing new clothing when a considerable loss is at stake. Generally, it is forbidden to knit or embroider during the Nine Days. However, if a woman is learning to knit in order to pursue knitting as a profession and earn a livelihood, then she may knit as part of her training during the Nine Days. Hacham Ovadia Yosef explained that teaching young women skills that they can use to earn a living and support their families is an important Misva – especially if these skills allow them to work from home and thus avoid compromises in Seniut (modesty) that are sometimes made when working outside the home. Therefore, it is entirely permissible to teach these classes during the Nine Days. Rav Shlomo Zalman Auerbach (Jerusalem, 1910-1995) was asked whether girls' summer camps that offer sewing and embroidery as activities may allow these activities to continue during the Nine Days. He replied that given the importance of attracting youngsters to summer programs run under religiously observant auspices, this may be allowed. If even a single knitting class is cancelled, Rav Shlomo Zalman said, it is possible that a girl or several girls will not want to join such a program, and will thus end up participating in programs that are not run in accordance with Halacha and Torah values. Therefore, the knitting activities can proceed as usual during the Nine Days. Women who knit for their emotional wellbeing, such as to keep themselves busy or as a way to effectively handle feelings of anxiety and the like, may knit during the Nine Days. Knitting for Misva purposes is allowed during the Nine Days. It is thus permissible to prepare threads for Sisit. Hacham Ovadia also ruled that if a pillow needs to be sewn to be used at a Berit Mila, this may be done during the Nine Days. Women who spin thread for a living may continue their work during the Nine Days. Producing threads does not bring joy like producing articles of clothing, and so this is permissible.