How to write a summary?

In scholastic and professional settings alike, you are likely to be asked to compose a summary of an article, essay, paper, report, or other document. Take the following steps to produce an effective outline.
Read the source content, and divide it into sections according to headings and subheadings or other delineation. For each section, highlight key points and statements, and note passages that themselves summarize the entire piece as well as those that are unnecessarily detailed or that digress from the main topic; the latter elements should be omitted from reference in the summary.
For each section, craft a single sentence that outlines that part of the entire work. After you have compiled these sentences, read through them to determine the thesis for the entire work, and then state the thesis.
Using these elements, construct a summary that begins with your thesis statement and outlines the entire work in the order in which the points are addressed in the original content; employ transitional words, phrases, and sentences for a smooth-flowing summary. When you are finished, check to make sure that your summary is significantly shorter than the original work. If it’s not, pare your summary to a more concise form.
In the summary, credit the original work and its author(s), cite any exact quotations (or be sure that you have paraphrased rather than directly quoted the original work), and refrain from interpretation. A summary is not the same as a critique, and it should state only what the author(s) wrote, not your opinions or extrapolated ideas about it.
Review for accuracy and for fidelity to the viewpoint of the original work, and revise to ensure that you have employed proper grammar, syntax, usage, style, and punctuation. Ask a classmate or colleague to evaluate it as well — not to edit or rewrite, but to confirm, without referring to the original work, that you have produced a cogent summary.