"And you shall speak to all who are wise hearted, whom I have filled with the spirit of wisdom, that they may make Aaron's garments to consecrate him, that he may minister to me in the priest's office." (Ex 28:3)

Aside from the fact that the priestly garments must be made "for honor and for beauty," the above verse also instructs us that they must be made with wisdom and understanding... for they must be produced in exact accordance with all the nuances of the Biblical requirements.

Furthermore, they must be made with a special intention in mind - namely, that they are being created for the sake of fulfilling G-d's commandment.

The priestly garments are not sewn, like other clothes. Each item is woven, seamless, of one piece. The only exception to this is the sleeves of the robe, which are woven separately and sewn onto the robe afterwards.