Exodus 28:1-4, 30-38
"Then bring near to you Aaron your brother, and his sons with him, from among the people of Israel, to serve me as priests--Aaron and Aaron's sons, Nadab and Abi'hu, Elea'zar and Ith'amar. And you shall make holy garments for Aaron your brother, for glory and for beauty. And you shall speak to all who have ability, whom I have endowed with an able mind, that they make Aaron's garments to consecrate him for my priesthood. These are the garments which they shall make: a breastpiece, an ephod, a robe, a coat of checker work, a turban, and a girdle; they shall make holy garments for Aaron your brother and his sons to serve me as priests. And in the breastpiece of judgment you shall put the Urim and the Thummim, and they shall be upon Aaron's heart, when he goes in before the LORD; thus Aaron shall bear the judgment of the people of Israel upon his heart before the LORD continually.
"And you shall make the robe of the ephod all of blue. It shall have in it an opening for the head, with a woven binding around the opening, like the opening in a garment, that it may not be torn. On its skirts you shall make pomegranates of blue and purple and scarlet stuff, around its skirts, with bells of gold between them, a golden bell and a pomegranate, a golden bell and a pomegranate, round about on the skirts of the robe. And it shall be upon Aaron when he ministers, and its sound shall be heard when he goes into the holy place before the LORD, and when he comes out, lest he die.
"And you shall make a plate of pure gold, and engrave on it, like the engraving of a signet, `Holy to the LORD.' And you shall fasten it on the turban by a lace of blue; it shall be on the front of the turban. It shall be upon Aaron's forehead, and Aaron shall take upon himself any guilt incurred in the holy offering which the people of Israel hallow as their holy gifts; it shall always be upon his forehead, that they may be accepted before the LORD.”