God gave specific instructions for every detail of Aaron’s garments, and then for the sons (Nadab and Abihu, Leviticus 10:1) to also have tunics, sashes and caps. They were to wear them when they entered the tent of meeting, or when they approached the altar to minister in the holy place.
Thoughts
I think there is a connection between these men being appointed by God to minister as priests and God’s instruction to make these garments ‘for glory and beauty’. What do you think, is there a connection?