Dissect the autobiography. While carefully reading the text, note moments that you find particularly honest, insightful or well-written. Keep a list of these moments in a notebook or on your computer. Don't forget to include page numbers in the list for easy reference. If you've already finished reading the book, return to the text to make the list.
Develop a thesis. Use your overall impression of the autobiography and your list of interesting moments to form a conclusion; pick between two and four arguments that support your conclusion. The thesis is generally between one or two sentences long and appears in the introductory paragraph.
Organize your notes by identifying details that support your arguments. Create a short list for each argument with supporting details. This is your outline.
Compare your thesis and arguments to what others have written about the autobiography. Book reviews in major newspapers and articles in academic journals are both good sources for the opinions of others. The opinions that support your thesis can be used to add depth to your argument. Include at least one opinion that opposes your thesis. Systematically refute that counterargument to further explain your opinion.
Write your critical analysis based on your outline. The outline is only a guide and can be revised as new ideas surface during the writing process. However, once you alter the outline, don't forget to revise the introduction.