Person and Tone Third person is generally most effective. First person can sound self-conscious, but if you decide it's appropriate in a particular case, use it without apology. Avoid cuteness of any kind. If you write well enough about literature worth writing about, you'll hold your reader without chicanery. If you fear sounding stuffy, use occasional contractions, plenty of specific details, and short sentences.
Documentation Use a standard documentation style and use it consistently.
English majors should prefer MLA style. Use parenthetical references within your text, reserve endnotes for commentary that does not fit in the body of the text, and provide a list of works cited with full bibliographical information. I've used a few endnotes in this handout to show you what I mean. Listing the works you've consulted suggests that you've done your homework. Under no circumstances would I consider Cliff's Notes or other such works a work suitable for a college student to consult.