Answer:
Carries in the haggis from the kitchens to the top table. This is usually done accompanied by bagpipes and clapping from the standing guests. Poosie Nancy then brings the haggis on its platter and puts it before the guest who is to deliver the "Address to a haggis". S/he will stab it at the appropriate point and cut it open. When the address is finished the haggis is then carried back to the kitchens by Poosie Nancy, again accompanied by bagpipes and clapping from the guests. In the kitchen it is then served up and returned to the tables plated up with neeps, and tatties, etc.
Poosie Nancy ran a hostelry that Burns frequented and is usually dressed as a waitress and usually wearing a mob cap.