After we discussed the chatat korbanot (sin offerings), the Mishnah is now going to talk about the olah, which is also part of the category of kodshei kodashim (most holy offerings). The reason it matters whether it's kodshei kodashim or kodashim kalim (offerings of lesser sanctity) has to do with the laws of me'ilah.
If somebody benefits from a korban (offering) by mistake, if they are violating it with kodshei kodashim, they have to bring an asham me'ilah (guilt offering for sacrilege) korban and pay the amount of benefit that they received, plus a one-fifth penalty, to the treasury of the Beit HaMikdash (Temple). If it was kodashim kalim, me'ilah, benefiting in a problematic way from the property of the Beit HaMikdash, only applies to the eimurim, the limbs that are thrown onto the Mizbeach (altar), and only after the zerikat hadam, the blood has been spilled or thrown onto the Mizbeach.
The Mishnah says we're talking about the olah, the korban that's fully consumed, fully burnt on the Mizbeach. It's within the category of—it's slaughtered in the north of the courtyard, like the rest of the kodshei kodashim, and the blood is caught in the north of the courtyard as well. The blood has two applications that are really four. That means the Kohen (priest) threw the blood twice: one time on the northeast corner of the Mizbeach, and one on the southwest corner of the Mizbeach, causing the blood to splash onto both sides of each corner, so that the two applications reach all four walls. When he's putting it on each corner, the applications really go to all four walls, the two walls connected to each corner.
U-te'una hefshet ve-nituach ve-kalil la'ishim. And the offering has to be skinned, cut into pieces, and burnt completely on the fire of the outer Mizbeach.