I don't have any hard and fast rules, but if it is a big complicated project I don't usually try and come up with a single coherent diagram of my thoughts. Instead, I start out with a node for the date, and a child node for a subject, and child node of that with a sentence or two concerning a topic I'm working on. If there are more details to it, problems, questions, etc. they become sub-nodes of that, and so on.
I don't usually change the details of nodes that I already worked on, but rather write what has changed in a new node with the same name but under a later date node. I find that it becomes a mess if I try and keep every node updated to what I currently think about it, because too much information builds up to efficiently do so. Also, a lot of what I write only make sense in the context of what I wrote on other subjects during the same time period, so if I change one, I end up having to rewrite more and more, which eventually becomes a big mess.
The main benefit is that I can go through my notes quickly, skipping minutia of topics I'm not interested in simply by not reading the details of a node. I used to use a text file, and that was a very big problem, because not only would the amount of text that I'd have to go through became daunting. Also, I sometimes found it hard to interpret what I wrote, which means I wouldn't know if it applied to the problem I was working on or not.
However, in contrast to the above, I do try and make a definitive structure if it's a small topic or a quick idea for a new project or something simple like vacation plans.
BTW, it also works very well for taking notes for a class or self-study.
I don't usually change the details of nodes that I already worked on, but rather write what has changed in a new node with the same name but under a later date node. I find that it becomes a mess if I try and keep every node updated to what I currently think about it, because too much information builds up to efficiently do so. Also, a lot of what I write only make sense in the context of what I wrote on other subjects during the same time period, so if I change one, I end up having to rewrite more and more, which eventually becomes a big mess.
The main benefit is that I can go through my notes quickly, skipping minutia of topics I'm not interested in simply by not reading the details of a node. I used to use a text file, and that was a very big problem, because not only would the amount of text that I'd have to go through became daunting. Also, I sometimes found it hard to interpret what I wrote, which means I wouldn't know if it applied to the problem I was working on or not.
However, in contrast to the above, I do try and make a definitive structure if it's a small topic or a quick idea for a new project or something simple like vacation plans.
BTW, it also works very well for taking notes for a class or self-study.