Determine the style of citation your instructor wants you to use for your current essay. Citation styles vary across disciplines. If you are writing an English paper, you might be expected to form citations using the Modern Language Association style. If you are writing a history paper, you might be expected to use the Chicago citation method. The instructor normally lists this requirement on your assignment sheet. Contact your instructor if it is not listed, or if his wishes are ambiguous.
Cite your previous essays as an unpublished work if you are using the MLA format. This falls under the "Dissertations and Master's Theses" citation section. Use this format: Your last name, Your first name. "Title of the Essay." Type of essay (for example, MA thesis). Name of the institution, date degree earned or year paper written. Medium of the paper (for example, print).
Cite your previous essays as unpublished dissertations if you are using American Psychological Association format. Use this format: Your last name, Your first initial. (Year essay written). Essay Title. (Type of essay). Name of the institution, location of institution.
Cite your previous essays as a thesis or dissertation if you are using the Chicago format. Use this format: Your last name, Your first name. "Essay Title." Type of essay, name of institution, year written.