"I said: 'O Mother of the believers! Tell me about the Witr of the Messenger of Allah ﷺ.' She said: 'We used to prepare his siwak and water for purification, then Allah (SWT) would wake him when He willed to wake him at night. He would use the siwak and perform wudu, then pray eith rak'ahs; not sitting until the eighth rak'ah, when he would sit and remember Allah (SWT) and call upon Him. Then he would say the taslim loud enough for us to hear.'"  

عَنْ وَتْرِ رَسُولِ اللَّهِ ﷺ قَالَتْ كُنَّا نُعِدُّ لَهُ سِوَاكَهُ وَطُهُورَهُ فَيَبْعَثُهُ اللَّهُ لِمَا شَاءَ أَنْ يَبْعَثَهُ مِنَ اللَّيْلِ فَيَتَسَوَّكُ وَيَتَوَضَّأُ وَيُصَلِّي ثَمَانِ رَكَعَاتٍ لاَ يَجْلِسُ فِيهِنَّ إِلاَّ عِنْدَ الثَّامِنَةِ فَيَجْلِسُ فَيَذْكُرُ اللَّهَ ﷻ وَيَدْعُو ثُمَّ يُسَلِّمُ تَسْلِيمًا يُسْمِعُنَا  

"I said: 'O Mother of the believers! Tell me about the Witr of the Messenger of Allah ﷺ.' She said: 'We used to prepare his siwak and water for purification, then Allah (SWT) would wake him when He willed to wake him at night. He would use the siwak and perform wudu, then pray eith rak'ahs; not sitting until the eighth rak'ah, when he would sit and remember Allah (SWT) and call upon Him. Then he would say the taslim loud enough for us to hear.'" (Using translation from Nasāʾī 1315)   

عَنْ وِتْرِ رَسُولِ اللَّهِ ﷺ فَقَالَتْ «كُنَّا نُعِدُّ لَهُ سِوَاكَهُ وَطَهُورَهُ فَيَبْعَثُهُ اللَّهُ لِمَا شَاءَ أَنْ يَبْعَثَهُ مِنَ اللَّيْلِ فَيَتَسَوَّكُ وَيَتَوَضَّأُ ثُمَّ يُصَلِّي سَبْعَ رَكَعَاتٍ وَلَا يَجْلِسُ فِيهِنَّ إِلَّا عِنْدَ السَّادِسَةِ فَيَجْلِسُ وَيَذْكُرُ اللَّهَ وَيَدْعُو»