In all cases, a commonplace is a method of compiling knowledge for later use. In digital or analog form, this continued growth of stored ideas and projects is a key driver of intellectual development. Any time you decide to work on a project, you should attempt to collect and categorise all information that is relevant and useful.
Methodically noting and filing resources is a sign of a mature and deliberate craftsman—it is an investment into future learning and projects. Before long, you will begin to reach the point where this collection generates projects and ideas with minimal effort; previously isolated ideas are consolidated and curiousity spurred on.
I now use Are.na as a Memory Palace, separating my channels into rooms. For example, I have a channel that I call the Computation Room. It’s pretty generic and includes any type of block that relates to computation.
If I notice a pattern in the computation room I create a more specific channel in that room. I think of that more specific topic as an object within the room.
Then there are the adjacent topics that I often find even more exciting to focus on. For those, I choose a name that corresponds with the nature of a room and also its size. For example I have a channel called the Visual Computing Observatory. In my head I am imagining an actual observatory where I am looking and observing and studying a given topic.
In order that the mind may not be taxed, moreover, by the manifold and confused reading of so many such things, and in order to prevent the escape of something valuable that we have read, heard, or discovered through the process of thinking itself, it will be found very useful to entrust to notebooks…those things which seem noteworthy and striking.