What does a Sacristan do? Sacristans set up for Masses and funerals. They are the ones that prepare the altar before mass. This includes caring for sacred vessels, vestments, and other liturgical items, ensuring they are clean, organized, and ready for use. They check supplies, host and wine. To become a Sacristan, reach out to one of the heads and schedule a training. Father will also call mandatory Sacristan meetings that you would be required to attend.