If you are required to use an object from the play to represent her, I would use the poppet (doll) for Abigail and the play's beginning and end. When the play opens, Abigail and the other Puritan girls are perceived by their community as having no more use than a doll. They are denied an education, offered only domestic work as a form of usefulness/employment, and bored. So, they go to the forest with Tituba to be entertained and to satiate their desire for romance and adventure.
Once Abigail begins her false accusations and has gained fame as the leader of the afflicted girls, she is no longer a doll to be controlled by others' whims--she is now the puppeteer or master of the poppet. The literal poppet made by Mary Warren is Abigail's means to accuse Elizabeth Proctor. At the end, Abigail steals her uncle's money and flees town, leaving behind a group of poppets who are no longer under her control but who now have to clean up her mess.