Sacristans arrive early before Masses to prepare all that is needed for the Mass.  Sacristans also assist during Masses and clean-up after.
 

• Sacristans should have a proper understanding of Christ’s Real Presence in the assembly gathered, in the Word proclaimed, in the priest and in the consecrated bread and wine. 
• Have an understanding of the order of the Mass, the role of liturgical objects and how they work together to convey the Real Presence of Christ
• To serve as a sacristan requires knowledge of the order of Mass and the ability to read and interpret special liturgical instructions. This necessitates and understanding of the Ordo.
• To serve as a sacristan requires knowledge of the proper names of liturgical objects, as well as their proper handling of liturgical objects both by the sacristan and by the Liturgy Ministers during the liturgical celebration