Use a reasonably-sized font: either 10 characters per inch or a 12 point font. And choose a font that is easy to read rather one that is decorative: "Arial," "Lucida," "Modern," "Palermo" or "Times New Roman" are some good choices. Scripted fonts are hard to read even if they do make your paper "look nice"; it is the content of the paper that is most important, and making it easy for your readers to understand that content is always a good choice.
Verify that you have included the three specific elements that MLA requires. Review page layout and general formatting. Double-check style for the citation of sources both within the text and in a works cited page. Additionally, MLA contains specific requirements for use of quotes and abbreviations. Generally, speaking quotes of three or four lines are included in the text within quotation marks. Longer quotations are indented 1 inch from the left margin of the paper. Both styles of quotes require the use of a citation including the last name of the author and the page number referenced.