Leviticus 4:16-18

16The anointed priest will bring some of the bull’s blood into the tent of meeting.

17The priest is to dip his finger in the blood and sprinkle it seven times before the Lord in front of the curtain.

18He is to apply some of the blood to the horns of the altar that is before the Lord in the tent of meeting. He will pour out the rest of the blood at the base of the altar of burnt offering that is at the entrance to the tent of meeting.