For each major point you make, you MUST have evidence of one sort or another. If the question involved is controversial, you can, and in some cases should, give evidence on both sides and analyze which position is most worthy or convincing, and why. For most essays in a literature class, however, presentation of the evidence supporting only your thesis is probably sufficient. Check with your instructor.
(for English papers)
Incident of plot. Beware of overdoing this. You only need to inform the reader of the elements in an incident that supports the point you’re making. Starting to tell an incident of plot often leads writers to continue telling the story beyond the single incident needed for development of a single point. Don’t fall into this trap. Tell only that scene: DO NOT GO ON. You want the reader to focus on your argument, not on the narrative.
Character Analysis. An examination of a character’s attitudes based on actions, interior monologue (the character’s thinking) and paraphrased dialogue can support your thesis. Use the accumulation of details to support your claim, but be sure the reader knows what claim you’re making about the character before you flood the reader with details. If you don’t, your writing will exhibit an analytic gap.
Examination of symbolism, images, or figurative language. While it is naive to assume that authors write by “planting” symbols to give “hidden meaning,” it is often useful to consider what repeated or emphasized objects, words, actions, colors, sensory details, Biblical references, and the like might suggest in relation to a work’s theme or message.
When you refer to any of these base the basis for your argument, try not to assume what the author “meant.” Instead it’s better word it along these lines: “The recurring image/symbol/etc of _______ suggests…”
Historical and cultural background of the time period. Here you can draw on what you know outside the work of literature, as well as what the author suggests about the conditions, mores, attitudes, social problems, values, and movements contemporary to the work.
**BE CAREFUL WITH THIS. In English papers, historical background can be abused as an easy way out of supporting a claim that should be defensible using the text as well.