Perform wudu
Pray the required Isha prayer
Sleep for some time if possible
Wake up during the last third of the night
Make intention to pray Tahajjud
Pray at least 2 rakahs
Recite Surah Al-Fatihah and any other Surah in each rakah
Pray in sets of 2 rakahs
End with Witr if you have not prayed it after Isha
Make du’a after الصلاة
Pray with humility and sincerity