– Regarding Tahajjud Prayer –
First start off with reciting the Dua for Tahajjud before starting the salah.
Then Pray 2 rakats of Salah each (without iqamah) and it can be prayed till 8 rakat, how much of that you want to pray for example, 2 rakat or 4 rakat or 6 rakat or 8 rakat is upto you but more is always better inshaAllah.
After Tahajjud Salah is done, it is the sunnah to end with three rakat witr and if time is short then end with one rakat of Witr salah.
Make Dua and ask for forgiveness and for Jannatul Ferdous and refuge against Hellfire.
It is best to pray Tahajjud Salah 1 to 1.5 hours (last one third of night) before Fajr starts.
As Allah (swt) comes down to the first heaven in the last one third of night and invokes us to ask for forgiveness and anything else we want that is good, it is best that we ask and take the opportunity of this Divine Blessing;
And from [part of] the night, pray with it as additional [worship] for you; it is expected that your Lord will resurrect you to a praised station.
Surah Al-Isra 17:79
-Allah Descends to the First Heaven Every Night
Abu Huraira reported Allah’s Messenger (ﷺ) as saying:
Allah descends every night to the lowest heaven when one-third of the first part of the night is over and says: I am the Lord; I am the Lord: Who is there to supplicate Me so that I answer him? Who is there to beg of Me so that I grant him? Who is there to beg forgiveness from Me so that I forgive him? He continues like this till the day breaks.
Sahih Muslim 758 b
-11 Rakat of Tahajjud
It was narrated from ‘Aishah that:
The Prophet (ﷺ) used to pray eleven rak’ahs at night, ending them with one rak’ah of witr, then he would lie down on his right side.
Sunan an-Nasa’i 1696
-Dua Before Tahajjud
Allahumma Lakal-Hamd. Anta Qaiyyimus-Samawati Wal-Ard Wa Man Fihinna. Walakal-Hamd, Laka Mulkus-Samawati Wal-Ard Wa Man Fihinna. Walakal-Hamd, Anta Nurus-Samawati Wal-Ard. Wa Lakal-Hamd, Anta-L-Haq Wa Wa’duka-Lhaq, Wa Liqa’uka Haq, Wa Qauluka Haq, Wal-Jannatu Han Wan-Naru Haq Wannabiyuna Haq. Wa Muhammadun, Sallal-Lahu’alaihi Wasallam, Haq, Was-Sa’atu Haq. Allahumma Aslamtu Laka Wabika Amantu, Wa ‘Alaika Tawakkaltu, Wa ilaika Anabtu Wa Bika Khasamtu, Wa ilaika Hakamtu Faghfir Li Ma Qaddamtu Wama Akh-Khartu Wama As-Rartu Wama’a Lantu, Anta-L-Muqaddim Wa Anta-L-Mu Akh-Khir, La ilaha illa Anta
O Allah! All the praises are for you, You are the Holder of the Heavens and the Earth, And whatever is in them. All the praises are for You; You have the possession of the Heavens and the Earth And whatever is in them. All the praises are for You; You are the Light of the Heavens and the Earth And all the praises are for You; You are the King of the Heavens and the Earth; And all the praises are for You; You are the Truth and Your Promise is the truth, And to meet You is true, Your Word is the truth And Paradise is true And Hell is true And all the Prophets (Peace be upon them) are true; And Muhammad is true, And the Day of Resurrection is true. O Allah ! I surrender (my will) to You; I believe in You and depend on You. And repent to You, And with Your help I argue (with my opponents, the non-believers) And I take You as a judge (to judge between us). Please forgive me my previous And future sins; And whatever I concealed or revealed And You are the One who make (some people) forward And (some) backward. There is none to be worshipped but you.
Sahih al-Bukhari 1120
-Cleaning Mouth with Siwak (Miswak) before Tahajjud
Whenever the Prophet (ﷺ) got up for Tahajjud prayer he used to clean his mouth (and teeth) with Siwak.
Sahih al-Bukhari 1136
-Surah Imran last 10 verse
Narrated Kuraib Maula Ibn `Abbas:
`Abdullah bin `Abbas said that he had passed a night in the house of Maimuna the mother of the faithful believers , who was his aunt. He said, “I slept across the bed, and Allah’s Messenger (ﷺ) along with his wife slept lengthwise. Allah’s Messenger (ﷺ) slept till midnight or slightly before or after it. Then Allah’s Apostle woke up, sat, and removed the traces of sleep by rubbing his hands over his face. Then he recited the last ten verses of Surat-Al `Imran. Then he went towards a hanging leather water container and performed a perfect ablution and then stood up for prayer.” `Abdullah bin `Abbas added, “I got up and did the same as Allah’s Messenger (ﷺ) had done and then went and stood by his side. Allah’s Messenger (ﷺ) then put his right hand over my head and caught my right ear and twisted it. He offered two rak`at, then two rak`at, then two rak`at, then two rak`at, then two rak`at, then two rak`at and then offered one rak`a witr. Then he lay down till the Mu’adh-dhin came and then he prayed two light rak`at and went out and offered the early morning (Fajr) prayer.”
Sahih al-Bukhari 1198