The laws of prayer and kiddush on Shabbat are numerous, so we will cover only those that pertain specifically to women.
The Shabbat Amida is comprised of seven berakhot. The first three and last three berakhot are identical to the corresponding berakhot in weekday Amida; however, instead of the thirteen middle berakhot, on Shabbat a special berakha about the sanctity of the Shabbat is recited.
Although it would have been possible to recite all the weekday berakhot of the Amida on Shabbat in addition to a special berakha in honor of the day, the Sages did not want to trouble people with lengthy prayer, so they shortened the Amida by replacing the middle thirteen berakhot with just one berakha. However, if one mistakenly began to recite the weekday berakhot and realizes in the middle of one of the blessings that it is Shabbat, she concludes that berakha and only then returns to the Shabbat liturgy; since in principal it would be acceptable to recite the weekday berakhot, once she already began reciting the berakha, it is proper that she finishes it (SA 268:2). 1
The Sages instituted a special berakha for each Amida of Shabbat: Atta Kidashta for Ma’ariv, Yismaĥ Moshe for Shaĥarit, and Atta Eĥad for Minĥa. One who accidentally mixes up one berakha with another, for example by reciting the Minĥa liturgy at Ma’ariv, still fulfills her obligation, because they all address the sanctity of Shabbat. However, if he mistakenly prays a weekday Amida instead of the Shabbat Amida, since she does not mention Shabbat, she does not fulfill her obligation and must pray again. If she realizes her error before finishing the Amida, she returns to the Shabbat berakha and continues from there to the end of the Amida (SA 268:5-6).
- While praying Musaf, if one mistakenly begins reciting the weekday berakhot and then realizes that she should be reciting Musaf instead, she immediately stops, even if she is in the middle of a berakha, since there is absolutely no need to recite weekday berakhot in Musaf (MB 268:5; Peninei Halakha: Shabbat, ch. 4 n. 1. ↩