‘He slew also the ox and the ram, the sacrifice of peace offerings, which was for the people, and Aaron's sons delivered to him the blood, which he sprinkled on the altar round about, and the fat of the ox and of the ram, the fat tail, and that which covers the innards, and the kidneys, and the covering of the liver, and they put the fat on the breasts, and he burnt the fat on the altar, and the breasts and the right thigh Aaron waved for a wave-offering before Yahweh, as Moses commanded.'
Aaron then offered the bull ox and the ram which were to be the sacrifices of peace offerings on behalf of the people. He slew them, his sons caught the blood, then they passed it to him for its application to the sides of the altar.
After this he burnt on the altar the fat and the vital parts, while the breasts and the right thighs he waved as a wave-offering before Yahweh. But while they belonged to Yahweh, as the waving indicated, for it was an offering made to Him, these were to be retained for the benefit of the priests. In this case because all the priests were involved in the peace sacrifices all would partake equally. Normally the thigh would belong to the officiating priest.
So, having been consecrated, Aaron's next immediate responsibility had been first for himself and then for God's people. We too when consecrated to God through salvation must watch for our own lives and then for the lives of others. We will need daily cleansing, but it should be followed by daily service. Our lives as His priests are to be wholly His, and to have ‘all the people' in mind.