When we approach a new subject of study one of the first steps we have to take is about the organization of the things we already know in that field and consider them like the pillars of our stock of knowledge. In this way we build a solid basis on which to put all the other notions. It is unlikely to know absolutely nothing about a topic, we often know much more than we think. Anyway, it is not mandatory to choose general concepts or basic information, although sometimes it is appropriate to do so. Instead, it is important to choose things that are clear for us and – after doing this selection – building around them our understanding and allocating our knowledge. Now I will provide some examples.
1) If a student doesn’t understand the first law of thermodynamics, which reads as follows: «The law of conservation of energy states that the total energy of an isolated system is constant; energy can be transformed from one form to another, but cannot be created or destroyed» we could first make clear to him the concepts of “energy”, “isolated system” and “constant” one by one, rather than trying to make him understand the principle as a whole. In fact, quite often people do not understand complex concepts because they have no clear idea about the basic concepts that compose them.
2) If a student cannot apply a grammar rule constructing new sentences in a foreign language, maybe we should find a phrase already prepared that respects the rule (and that he is able to perfectly understand) and advise to build other phrases around this model. For example the French sentence «vous devez me excuser» (you’ll have to excuse me) could be the base to assemble many other phrases, different in meaning but similar in structure like these: «tu peux me écouter», «il doit vous aider» etc.
3) Reviewing the notions that you already know about a subject you have to realize if they are clear, exact and what relationships they have among themselves. In this manner these contents become your pillars in that specific field of knowledge. So, once you do this, you could go on to learn the subject. At this stage anytime you find something new or strange ask yourself what relations this new information has with your personal pillars. The more links you find, the greater the understanding.
These three simple strategies can introduce some advice that is often given by teachers to students, but that is almost never listened to by the latter. The advice is this: ask questions to yourself. But usually people don’t know what kind of things they have to ask themselves: that’s why the previous three strategies are useful, since they give a method to follow to structure the questions. In summary: the first thing to ask is about what links, connections, relations there are between the new information that we want to acquire and the pillars of the structured knowledge that we already have.
Then we need to continue the formulation of the questions on what may be the aspects, the characteristics of the new information to allow us to remember it. Even more, we should ask ourselves questions that allow the deconstruction and then the restructuring of the information, in such a manner that the processing transforms information into content which can be more integrated in our stock of knowledge and our universe of memory.
The necessity of having to remember certain information is often born from questions and doubts that we set ourselves. Asking questions to ourselves while we learn, makes it easier to recall later, especially if the questions follow a precise logic. Over the past two centuries the 'rule of 5W' has been widely circulated and it has become the basic tenet that every journalist should use to write their own articles. The 5W means: Who, What, When, Where, Why.
In the early days of modern journalism, when the correspondent dictated the news via telegraph (so that editors could then draft the article in the press), he had to sum up most of the items to report the event since sending messages was very expensive. In order to do this the reporter had to report in a very concise, but complete way, the salient features of the event: who is the author of the fact, what constituted the fact, when, where and why it was committed.
To observe this order in the messages it gives the opportunity to those who receive them to rebuild the news in its entirety. Starting from these few, but cardinal elements you can also reconstruct a very complex story without fear of making mistakes. How to use this method to improve our approach to learning? First, this procedure guarantees an order not only in the way you learn, but also in the mental disposition in which you can organize the information. Secondly, it allows to revise the information with the aim of arranging it in compliance to our cognitive and learning style. Now I’ll make an example in order to expose a mnemonic strategy.
Imagine that the reporter on the site of the news and the editor in the newspaper office are not two separate individuals in two different places, but ourselves at two different times: when we learn contents of information (i.e. we have been sent to the place of the event) and when we recall the stored information (that is: when we are preparing to rebuild the news article for printing). Here, memorizing something defining it by the application of the “5W rule”, facilitates the time when we go to evoke it since we passed the information to the headquarters of our newspaper (out of metaphor: memory) with the necessary coordinates. Simply ask ourselves the questions about what we have learned in the same order as it is arranged in the “5W rule”; first: «who?»; second: «what?» etc. For example, for a football match the answer of «who?» it could be “Manchester United vs Real Madrid”; for «what?» we say “the final of the Champions League” and so on. However, not always we will find information that fits each question (much depends on the nature of the data to be stored), but it’s always useful to proceed so. This is a little role-playing that is convenient to act on our own or with a classmate or another student that has to study our same subject.
Anyway, already in the "5W" formula you can easily identify a small mnemonic device that is the choice of using all words that begin with the letter W. These words represent the plot line to write an essay or any other literary composition as well as a newspaper article. Ultimately, they can frame any topic. In fact, asking ourselves these questions concerning any subject of study and/or description, helps define it in the right and synthetic terms.
This rule has an obvious mnemonic value: it gives an order to the material that is to be reported; it avoids the problem of redundancy, or unnecessary repetition of what has already been said, it gives a help for the opening words (incipit), and a starting point for the invention (finding topics and ideas to expose and supporting a thesis). Aquinas, in the Summa Theologiae  , as well as incorporating an ancient rhetorical tradition, anticipates what will be centuries after the above-mentioned rule of 5W, however attaching other important elements.
Indeed, he had as a main purpose (in his schematic description of the appropriated questions to circumscribe a fact) a moral one. It does not suffice to define the moral value of an action (or omission) limiting ourselves to asking who, what, where, when and why - it should also clarify the circumstances in which the act (or omission) is done. Circumstances that are both of the acting subjects and of the object that suffers the action. There are countless circumstances in which the person was able to take action, each of which confers to the action a moral and, in our case, a mnemonic value different from all the others. St. Thomas distinguishes 8 basic elements in an action (and therefore we should try to apply these criteria when we're going to form mental images of actions to remember). Here is a table comparing the rule of 5W and elements of Aquinas:
- QUIS – Who (“5W rule” and Aquinas elements)
- QUID – What (“5W rule” and Aquinas elements)
- QUANDO – When (“5W rule” and Aquinas elements)
- UBI – Where (“5W rule” and Aquinas elements)
- CUR – Why (“5W rule” and Aquinas elements)
- QUANTUM – How much/many (only Aquinas elements)
- QUOMODO – In what way (only Aquinas elements)
- QUIBUS AUXILIIS – By what means (only Aquinas elements)
 From Wikipedia encyclopedia entry First law of thermodynamics, saved Saturday, November 14th, 2015.
 See P. Fabiani, Metaphor and Memory, Libriliberi, Florence, Italy, 2015, p. 90.
 «Respondeo dicendum quod Tullius, in sua rhetorica, assignat septem circumstantias, quae hoc versu continentur, quis, quid, ubi, quibus auxiliis, cur, quomodo, quando. Considerandum est enim in actibus quis fecit, quibus auxiliis vel instrumentis fecerit, quid fecerit, ubi fecerit, cur fecerit, quomodo fecerit, et quando fecerit. Sed Aristoteles, in III Ethic., addit aliam, scilicet circa quid, quae a Tullio comprehenditur sub quid. Et ratio huius annumerationis sic accipi potest. Nam circumstantia dicitur quod, extra substantiam actus existens, aliquo modo attingit ipsum. Contingit autem hoc fieri tripliciter, uno modo, inquantum attingit ipsum actum; alio modo, inquantum attingit causam actus; tertio modo, inquantum attingit effectum. Ipsum autem actum attingit, vel per modum mensurae, sicut tempus et locus; vel per modum qualitatis actus, sicut modus agendi. Ex parte autem effectus, ut cum consideratur quid aliquis fecerit. Ex parte vero causae actus, quantum ad causam finalem, accipitur propter quid; ex parte autem causae materialis, sive obiecti, accipitur circa quid; ex parte vero causae agentis principalis, accipitur quis egerit; ex parte vero causae agentis instrumentalis, accipitur quibus auxiliis.» Sancti Thomae de Aquino Summa Theologiae  Iª-IIae q. 7 a. 3 co.