The MLA citation style discourages extensive use of footnotes and endnotes. After all, the whole point is to cite your source in the body of the text.
However, sometimes a note may be useful to add some information without adding a digression or interrupting the flow of the argument.
There are two types of notes that you can add: content notes and bibliographic notes. There is a lot of overlap between them, but perhaps you’ll find the distinction useful.
A content note adds some further explanation or information that doesn’t fit in the body of the text:
Dietitians are still divided on some key questions. Should the job title be spelled “dietitian” or “dietician”?¹ Is the tomato a fruit or a vegetable?² When does obesity become morbid? However, everyone does agree that forcing children to eat Brussels sprouts is immoral.
¹Like most practitioners (which is also spelled without a “c”), we prefer “dietitian.”
² While the issue appears to be settled in favour of the fruit camp, Olaf B. Ferguson notes that “some Transylvanian critics remain stalwart holdouts” (44). For a fruitful discussion of the issue, see especially Legume and Leek 79-99.
Try to keep such notes to a minimum. If a detail is important, try incorporate it in the body of your text.
If you find that you need to cite additional sources, you may want to add a bibliographic note. You can see some of this already in the second note above. Here is another example:
³ The same observation is found in subsequent textbooks (e.g., Emerald 101, Luxemburgher 22). Only recently has there been some questioning of the traditional paradigm. See Islander 44 for some probing questions.
A bibliographic note thus allows you to add further references, as well as commentary on them.
The MLA Handbook (8th ed.) says very little about how to format notes. However, it’s clear that you should use arabic numbering (1, 2, 3, etc.). In addition, text in footnotes is usually in a smaller font (e.g., Times New Roman size 10).
It’s up to you (or your instructor) whether you use footnotes or endnotes. If you choose the latter, place them on a separate page, after the text and before the Works Cited. Adding a title such as “Notes” would be a nice touch.
In the end, there are just two essential rules to remember. First, the MLA guidelines suggest you minimize the use of notes. Secondly, if you cite anything in a note, follow the regular rules for in-text citations.