Rule 3.

We have found that the inverted triangle is the best shape for laying out notes. You start each triangle with a new key point, jotting down the point in four or five headline words, perhaps in capital letters.  Supporting points follow underneath in stepped fashion. By the very nature of a note ('brief record of facts, impressions or topics', Australian Concise Dictionary) you don't write proper sentences, but headings, subheadings and phrases, which will remind you later of the things which are important, interesting or amusing.  The empty space created by the triangle leaves room for you to add new material or relevant comments later.

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Rule 6.

It is worth noting what notes are not.  In the old days, teachers dictated the notes and students were expected to learn them and be able to repeat them parrot-fashion upon request (whether or not the students actually understood what the notes were about). Today students make their own notes.  There is no point in making so many notes that you cannot absorb their information or cannot cope with them at revision time.  You have to be your own editor as you go along, discarding unnecessary details, and noting only the real 'meat' of what you are hearing or reading.

It is not easy, and some people are frightened of leaving out vital information, but constant practice makes it much easier (and you can get all the practice you want by making notes from radio news bulletins or talk-back shows). It is wise to develop the habit of comparing your notes with those of some friends - if they have taken notes which you missed, and which, with further thought, you think seem valuable, you can always add them on to the bottom or the side of your own notes, and vice versa.