How did the Prophet, may God's prayers and peace be upon him, sleep? Did he sleep on a bed or on the ground? And did he recite a specific supplication when he intended to sleep?

The Prophet Muhammad (peace be upon him) used to sleep on various surfaces, such as a mattress, a mat, the ground, a leather spread (niṭʿ), and a bed, and sometimes on a black garment. His mattress and pillow were made of leather stuffed with palm fibers. He would sleep in the early part of the night and rise in the latter part, and his eyes would sleep but his heart would not.

Before sleeping, he would remember Allah by saying: "O Allah, in Your name I live and die," and "Praise be to Allah who fed us, gave us to drink, sufficed us, and sheltered us. How many are there who have no provider and no shelter!" and "O Allah, Lord of the heavens and the earth, and Lord of the Great Throne..." He would also cup his hands together, blow into them, recite the Muʿawwidhat (Surahs Al-Falaq and An-Nas), and then wipe his body three times. He would sleep on his right side, placing his right hand under his right cheek, and say: "O Allah, protect me from Your punishment on the Day You resurrect Your servants."

Upon waking, he would say: "Praise be to Allah who has given us life after causing us to die, and to Him is the resurrection," and he would use a miswak. He might also recite the last ten verses of Surah Aal Imran and remember Allah with praise and supplication. His sleep was moderate, which is the most beneficial type of sleep, and it amounted to one-third of the night and day.