Read the work carefully. Identify the main arguments that the author makes, as well as the main point that the arguments back up. Write down a summary of the author's thesis and supporting arguments.
Analyze the work and ask questions about the validity of the author's sources --- whether the supporting arguments support the thesis, whether the author's use of his thesis and evidence led you to the same conclusions as the author, whether the author's evidence was accurate and what the author's bias is. You can also include information on whether and how the author includes information from other opinions of the topic he writes about.
Write down your answers to these questions, using evidence from the work to support your ideas. Write down quotes or paraphrases from the work that bolster your arguments. You will use these later when you write the body of the paper. Note page and section numbers to include in a bibliography or in the text of your work.
Write your critique's introduction, which should include the name of the work and the author, when it was published, and a short summary of the work. It should also contain a thesis of your own that summarizes your reaction to it.
Write the body of the critique to include paragraphs about the questions you answered. Back up your arguments with evidence from the work. Cite other critiques of the work to support your ideas as well. Avoid summarizing the work you are critiquing. The main purpose of a critique is to examine a work, not to summarize it in detail.
Explain in your conclusion how the author's works affects his audience overall, whether you agree with his work's thesis and whether and how his work is significant.
Include a bibliography or footnotes or endnotes to cite your sources of both the work and other critiques and summaries that you include in your critique.