I tried taking similar notes in a text file/org-mode, but it didn't work for me because it's not free-flowing and not expressive enough. Probably, an iPad or a tablet with a stylus pen would work just as well, but paper is still easier and cheaper. :)
I could just as easily use a markdown file or similar for it, but I find writing quick and fairly effortless and I really enjoy using a nice combination of fountain pen and quality pad. It can also be nice to have something I can look at from time to time that isn't emitting light and causing eye strain.
It's taken me years to settle on this system as an optimal ADHD memory prosthetic.
I get inspired by Pac-Man designer Toru Iwatani's early sketches for the game. Every pixel block, every animation frame, was pre-visualized on paper before being input into the machine in 6502 Assembly Code!
But I have to say, I've received the new ReMarkable2 [1] about a week ago, and it's awesome and might replace my doodling notebook - I mostly draw with just black ink anyway. I made this quirky Xmas "card" [2] with it.
(It won't replace the paper journal for writing, though.)
2. https://juanuys.com/assets/posts/2020-12-19-twenty-twenty/Xm...
My notepad environment is chaotic and temporary. Some notebooks from workplaces, some I've picked up at department stores. Some full, some empty. None ever get refered back to, I have neither the time nor inclination. If an idea doesn't bare fruit quickly, its next step in becoming a bigger thing, then it deserves to die.
Since others are talking about what notebooks they use I will too. I second the observation that caring too much about a special kind of notebook or how you use it is a waste of time. I just use blank printer paper and a felt tip architectural pen - I scan notes that I think are relevant and organize them in with a tool I wrote. (parents were architects so I'm forever addicted to this kind of pen - fuck ballpoint anything other than Pilot G2's).
Aside from that, I always have a scratch pad and plenty of post-it notes lying at hand. The former for any quick-and-dirty doodling, the latter for my to-dos.