How precisely is Tahajjud prayer performed, and what are the supplications authentically reported from the Prophet, peace and blessings be upon him, concerning it?

Tahajjud prayer consists of two rak'ahs, then two rak'ahs, and it is sunnah to conclude it with a single rak'ah of Witr. The Prophet, peace and blessings be upon him, did not exceed eleven or thirteen rak'ahs. As for the supplications and remembrances, they include the opening supplication (Du'a al-Istiftah), and what Al-Bukhari transmitted from Ibn Abbas, may Allah be pleased with both of them, that when the Prophet, peace and blessings be upon him, stood up at night to perform Tahajjud, he would say: "O Allah, to You be praise; You are the Sustainer of the heavens and the earth and whoever is in them..."