A summary condenses a long passage of text into important ideas. Details are usually omitted.

You restate the author's ideas in your own words.

To summarize, read the author's words and put the text down. Using your memory, explain the passage in your own words. Re-read the author's words and review your own so you get it right. You don't want to misrepresent the author — that would be plagiarism.

A summary should be factual. Maintain your objectivity. Do not use emotion to strengthen your arguments. It may alienate your audience and lose their support of your thesis.

If you want to include an opinion or two in your paper, fine — but clearly distinguish them from any summaries that you write.