Bismillahir rahmanir raheem
Narrated Hudhaifa : Whenever the prophet got up for Tahajjud prayer he used to clean his mouth with siwak .
Narrated ‘abdullah bin ‘Umar (R) : A man said , “O Allah’s Apostle(S) ! How is the prayer of the night ?” He said , “Two rakat followed by two Rakat and so on , and when you apprehend the approaching dawn , offer one raka as Witr .”
Narrated Ibn Abbas : The prayer of the prophet used to be of thirteen Rakat , i.e. of the night prayer .