the Prophet said about the Mustahadah that she should: "Leave the Salat for the days of her period which she menstruates in, then perform Ghusl, and perform Wudu for every Salat, and observe Saum and perform Salat." (Using translation from Tirmidhī 126)
أَنَّهُ قَالَ فِي الْمُسْتَحَاضَةِ تَدَعُ الصَّلَاةَ أَيَّامَ أَقْرَائِهَا ثُمَّ تَغْتَسِلُ وَتَحْتَشِي كُرْسُفًا وَتَوَضَّأُ عِنْدَ كُلِّ صَلَاةٍ