"One of the sunnahs of the prayer is to spread your left foot beneath you, and hold your right foot upright."
Sunan an-Nasa'i Book 12, Hadith 129
← Previous Hadith They prayed behind Abu Hurairah, may Allah (SWT) be pleased with him, and he when he bowed, he said the Takbir, when he raised his head he said: 'Sami Allahu liman hamidah, Rabbana wa lakal-hamd. Then he prostrated and said the takbir, then he raised his head and said the takbir, then he said the takbir when he stood up following that Rak'ah. Then he said: 'By the One in Whose Hand is my soul, I am the one among you whose prayer most closely resembles that of the Messenger of Allah (ﷺ). And this is how he continued to pray until he left this world."

Sunan an-Nasa'i Book 12, Hadith 128 Next Hadith → His father (Ibn 'Umar) said: "One of the sunnahs of the prayer is to hold the right foot upright and point its toes toward the Qiblah, and to sit on the left foot."

Sunan an-Nasa'i Book 12, Hadith 130