Hadith no. 460 is a repeat. Read it here: Debt and Ihsaan.
Ibn ‘Umar said, “While the Prophet was on the pulpit, a man asked him how to offer the night prayers. He replied, ‘Pray two Rakat at a time and then two and then two and so on, and if you are afraid of the dawn (the approach of the time of the Fajr prayer) pray one Rak’a and that will be the witr for all the Rakat which you have offered.” Ibn ‘Umar said, “The last Rakat of the night prayer should be odd for the Prophet ordered it to be so.
Narrated Ibn ‘Umar:
A man came to the Prophet while he was delivering the sermon and asked him how to offer the night prayers. The Prophet replied, ‘Pray two Rakat at a time and then two and then two and so on and if you are afraid of dawn (the approach of the time of the Fajr prayer) pray one Rak’a and that will be the with for all the Rakat which you have prayed.” Narrated ‘Ubaidullah bin ‘Abdullah bin ‘Umar: A man called the Prophet while he was in the mosque.
So it’s easy. 2 rak’aat at a time. And when you’re done, finish up with a witr (single rak’at).
Ibn Hajar says:
There was no specific time in which the Prophet (peace and blessings be upon him) would perform his late night Prayer; but he used to do whatever was easiest for him.
Narrated Abu Huraira:
Allah’s Apostle (p.b.u.h) said, “Our Lord, the Blessed, the Superior, comes every night down on the nearest Heaven to us when the last third of the night remains, saying: “Is there anyone to invoke Me, so that I may respond to invocation? Is there anyone to ask Me, so that I may grant him his request? Is there anyone seeking My forgiveness, so that I may forgive him?”
`Amr ibn `Absah claimed that he heard Muhammad saying:
The closest that a servant comes to his Lord is during the middle of the latter portion of the night. If you can be among those who remember Allah the Exalted One at that time, then do so.—At-Tirmidhi