The problem with a page full of yellow
Highlighting feels productive. The marker moves, the page changes color, and it seems like you are doing something. The trouble is that it asks very little of your brain. When most of a paragraph is highlighted, you have not decided what matters; you have only decorated the page. Some research on study techniques has described highlighting and underlining as having limited benefit compared with methods that make you recall or explain material, though the findings depend on how the marking is done.
That does not mean you should stop marking texts. It means annotation should be selective and should leave behind something you can use. Think of it as leaving a trail for your future self, who will come back to the page weeks later with an exam, essay or project in mind.
Start with a purpose
Before you mark anything, ask what you are reading for. The answer changes what is worth marking.
- Reading to understand a topic: mark definitions, claims and the connections between them.
- Reading for an essay: mark evidence, quotations you might use, and points you disagree with. Note the page number and source details at the time, because it is much harder to find them later when it comes to citing sources.
- Reading for an exam: mark what you could be asked, and anything you would need to be able to explain from memory.
A few seconds of deciding on a purpose usually cuts the amount of marking in half.
Read first, mark second
One of the simplest fixes is to read a paragraph or section completely before marking anything. On the first pass you often cannot tell what the main point is. Once you reach the end of a section, you can go back and mark the one or two things that actually carried the argument. This also stops you from highlighting every sentence that looks important at the moment you read it.
A workable rule: no more than a few marks per page, at least to begin with. If that feels too strict, it is a sign you may be marking support rather than the main idea.
Use margins for thinking, not just marking
A highlight shows that something is there. A margin note shows what you made of it. Useful margin notes are short and varied.
- Paraphrase: restate the point in a few words of your own. If you cannot, you have probably not understood it yet.
- Label: write “definition”, “example”, “cause” or “counterargument” next to a passage.
- Question: write a question that the passage answers, such as “Why does this happen?” Later, these become prompts for active recall.
- Connect: note links to other chapters, lectures or readings.
- Challenge: write “but what about…?” when something seems weak. This kind of response is basic critical thinking, and it helps you read more actively.
Short is better. If a margin note takes longer than a sentence, move it to a separate notebook or document.
A simple symbol system
A small set of marks, used consistently, makes later review much quicker. For example:
- Underline a key term or phrase, not a whole sentence.
- Star a main idea.
- Question mark something you do not understand.
- Box a definition.
- Numbers in the margin for steps or a list of reasons.
- Arrow to link a cause to an effect or one idea to another.
You do not need these exact symbols. Choose a few, write them in the front of the book or at the top of your document, and stick to them for a few weeks. If your system gets complicated, you will stop using it.
Using more than one color
If you like color, give each color a job. Perhaps yellow is for definitions and green for examples. The limit is the number of colors you can remember without checking a key; two or three is usually plenty. More than that and the system becomes a puzzle.
Annotating digital texts
Most reading software lets you highlight and add comments. The same principles apply, with a few extras.
- Digital highlights can be exported or listed in one place, which makes it easier to review them together. That is a point to consider when comparing digital note tools.
- It is tempting to highlight faster because there is no cost to doing so. Keep to the same rule of reading first, marking second.
- Typing a short comment takes a moment, but it is the part that makes the annotation useful.
If you are reading something you do not own, such as a library book, use sticky notes or a separate sheet instead of writing in it.
Turning annotations into review material
Marking is only half the job. Here is a short routine for the end of a reading session.
- Flip back through the pages and scan only your marks and margin notes.
- Write down three to five key points in your own words, ideally without looking.
- Check them against the text and fix anything you missed.
- Copy your margin questions onto cards or a list for later practice.
Doing this once a week, rather than the night before an exam, spreads the effort out. If you keep a study journal, a few lines about what you learned from each reading can sit there alongside the marks.
A note on essay work
When you are annotating to prepare writing, include a thread of your own thinking. Mark where the author states a claim that could support your thesis statement, where the evidence is thin, and where you might disagree. Gathering these notes in a short list before drafting makes essay planning easier, since you start with real material rather than a blank page.
Quick checks
If you are unsure whether your annotation is working, ask yourself:
- Could someone skim only my marks and understand the main argument?
- Do my margin notes contain any of my own words?
- Do I know why each mark is there?
- Is there more unmarked text than marked text?
If the answer to most of these is yes, your annotation is probably doing its job. If not, try marking less and writing more. Keep in mind that no marking style guarantees better results, and what works can vary by subject and by person.