It's how to say a Low Mass! Incidentally it seems that the paten is what the priest has the hostia on before it is consecrated.

Prepare the missal, if necessary, marking the appropriate pages with ribbons. Wash your hands, saying the prayer "Da, Domine" and then, if necessary, prepare the chalice and paten. Then make the sign of the cross and as you vest say the vesting prayers. (It is expected that the priest is already wearing a cassock. If not it should be put on first, it is unbecoming to put vestments on over ordinary outdoor clothes.)

The amice is put on first, followed by the alb, the cincture, the maniple, the stole and lastly the chasuble. The cross on the amice, maniple and stole is first kissed before the vestment is put on. When putting on the amice it should first be placed on the head and then at once lowered and arranged around the neck. When vested put on the biretta.

Which matters little to most of you but somewhat to one. My favorite part is the little bit about the cassock. "Unbecoming". Oh well, hope springs eternal. Good thing it's a theological virtue and not an emotion.