Assitant: assists in leading the service, serves as chalice bearer
Reader 1: reads the OT, reads the Psalm, and takes the offering
Reader 2: reads the NT and leads the prayers

Assistant: accompany the Celebrant in the chancel, read the Gospel, lead the congregation in the creed, and serve at communion as a chalice bearer. If there is no Reader 1 then the assistant will fulfill the role of Reader 1.
Reader 1: Read the first reading, lead the prayers of the people, and assist the Celebrant at the table during communion - accompany the Celebrant into the sanctuary during the offertory and serve as a chalice bearer.
Reader 2: Lead the psalm, read the second reading, and take the offering. When an additional chalice bearer is required Reader 2 will bring the offering to the table and then stay there to serve during communion.