An escort is a citizen of the Capitol whose main duty is to accompany the tributes of their assigned district and teach them how to behave properly, and to help them fit in with the guide lines of the Capitol. They have dozens escorts of tasks assigned to them around the time of the annual Hunger Games.
If the escort's tribute is a victor, the escort's job includes "escorting" the victor on the Victory Tour. After this, the escort may be promoted to a higher ranking district for the next year's games, or they might choose to stay with the district that they were with previously.
She would always make announcements and schedule to prepare and get ready for the day ahead of them. Although Effie cared about her tributes, she never had high hopes for any tributes from District 12 because of their poor living conditions.