"At the end of the last two rak'ahs of the prayer, the Prophet (ﷺ) would move his left foot forward and sit on his left buttock, Mutawarrikan, then he would say the taslim.
Sunan an-Nasa'i Book 13, Hadith 84
← Previous Hadith Abdullah bin Buhainah told him that the Messenger of Allah (ﷺ) stood up following two rak'ahs of Zuhr and did not sit down (for tashahhud). When he finished the prayer he prostrated twice, saying Takbir for each prostration, while he was sitting, before he said the taslim, and the people prostrated with him. (He did that) in place of the sitting that he had forgotten.

Sunan an-Nasa'i Book 13, Hadith 83 Next Hadith → "I saw the Messenger of Allah (ﷺ) raise his hands when he started to pray, and when he bowed, and when he raised his head from bowing. And when he sat, he would ay his left foot on the ground and keep his right foot upright, and he placed his left hand on his left thigh, and his right hand on his right thigh, making a circle with his middle finger and thumb, and pointing."

Sunan an-Nasa'i Book 13, Hadith 85