Layer one: highlight the most important sentences

On first or second reading, highlight the sentences that carry the most signal in this note.

Why it works

A raw note contains both high-signal and low-signal material in approximately equal proportions. Layer-one highlighting forces a quick curation pass that separates the memorable from the contextual. The act of selecting (rather than passively re-reading) also deepens processing — you must evaluate each sentence rather than skim over it, which improves subsequent recall of the highlighted material.

How to do it

1. Open the note and read through it with one question: which sentences would a future version of me most want to see quickly?
2. Highlight those — typically 10–20% of the total content.
3. Do not highlight comprehensively; err toward under-highlighting so the highlights stand out.
4. Do this on first return (when you use the note for a real purpose), not systematically across every note you save.

Evidence

Elaborative interrogation — asking "why is this important?" while reading — reliably improves recall compared with passive re-reading. Layer-one highlighting operationalizes a similar evaluative question for each sentence, deepening processing beyond simple exposure. (observational)

Generic highlighting (underlining most of a passage) does not improve recall over passive reading; the value is in selective, evaluative highlighting. The layer-one practice requires genuine selection, not comprehensive marking.

Sources

• Dunlosky et al. (2013), improving students’ learning with effective learning techniques, Psychological Science in the Public Interest

Common mistake

Highlighting too broadly — marking every sentence that seems relevant — so the highlights cover 60–70% of the note and provide no compression at all.