How to write a summary you'll actually remember

Making a summary is the most popular study technique in the Netherlands, and at the same time the one that is most often done wrong. The problem: most summaries are copied-out textbooks. You spend hours on them, it feels productive, but your brain has barely joined in. Here's how to make a summary that will really help you in the test.

The main rule: book closed, then write

The difference between copying and summarising comes down to one simple action: closing the book. Read a paragraph carefully, close the book and only then write down what the core point was, in your own words. If you skip something or can't remember it, check the book and fill in the gaps. That small struggle to write it down from memory is the learning. Anyone who summarises with the book open beside them is just copying text from left to right.

Shorter is better: aim for a third

A summary that is almost as long as the chapter isn't a summary. Rule of thumb: a maximum of one third of the original text, preferably less. That forces you to choose what is really important, and that choosing is thinking work again, which helps your memory. Ask yourself about every sentence: would the teacher ask a test question about this? No? Leave it out.

Give it a structure you can picture

A good summary isn't a wall of text but a map of the chapter. Use the headings from the book as your headings, use arrows for cause and effect, list items one under the other and leave white space between the blocks. Concepts you need to know get a fixed place, for example always underlined with the definition after them. In the test, you'll literally see that page in front of you.

Highlighting is fine, but use it sensibly

Highlighters are useful in the stage before summarising, for fishing the core out of the text. Two rules keep it worthwhile. First read the whole paragraph, then highlight: otherwise you colour in sentences that turn out to be side issues. And keep it to a fifth of the text at most, with a fixed colour code, for example yellow for key concepts and green for examples. A page that glows all over mainly shows that no choices were made.

The summary is the beginning, not the end

This is where it goes wrong for many students: the summary is finished, so the studying feels done. But making a summary is the first round of learning; the second is testing yourself on it. Cover parts with your hand and say what was there, or turn the key concepts into flashcards. Only when you can retell the content without the summary are you ready.

When does summarising work, and when doesn't it?

Summarising is strong for subjects with a lot of text and connections: history, biology, geography, economics. For vocabulary it's clumsy (flashcards are faster there) and for maths it hardly works: there you learn by doing problems, not by copying out theory. So choose your technique subject by subject, not out of habit.

Read also: Flashcards or summaries: which study technique works better? and What is the best way to study for a test?