משנה אויף ויקרא 6:3

The one who had merited to clear the ashes, would get ready to clear the ashes. They said to him: “Be careful not to touch any vessel until you have washed your hands and feet from the laver. See, the fire-pan is in the corner between the ascent and the altar on the west of the ascent.” No one entered with him, nor did he carry any light. Rather, he walked by the light of the altar fire. No-one saw him or heard a sound from him until they heard the noise of the wooden wheel which Ben Katin made for hauling up the laver, when they said, “The time has come.” He washed his hands and feet from the laver, then took the silver fire-pan and went up to the top of the altar and cleared away the cinders on either side and scooped up the ashes in the centre. He then descended and when he reached the floor he turned his face to the north and went along the east side of the ascent for about ten cubits, and he then made a heap of the cinders on the pavement three handbreadths away from the ascent, in the place where they used to put the crop of the birds and the ashes from the inner altar and the ash from the menorah.

How was the olah of a bird sacrificed? He [the priest] ascended the ramp, and turned to the surrounding walkway, and made his way to the southeast horn. There he pinched its head at the back of the neck, and severed it, and drained out its blood on the wall of the altar. He took the head, turned the part where it was nipped to the altar, saturated it with salt, and threw it on to the fires [of the altar]. Then he came to the body, and removed the crop, the feathers, and the entrails that came out of it, and threw them on to the burning place. He tore [the body], but did not sever it in half, but if he did sever it, it is still valid. Then he saturated it [the body] with salt, and threw it on to the fires of the altar.