So pleased to see the Leuchtturm 1917 dotted grid at the top of this list. It's been my go-to notebook for the last few years. It comes with some nice stickers for labeling so that you can find past notebooks on the shelf. Lots of colors are easily available on Amazon.
The Leuchtturm is my go-to as well for the last few years. I’m also glad they are very easy to source.
I like to have mine around for jotting ideas down and drawing diagrams. I don’t have a system or anything. I think I used to be far more prescriptive about what I put in it but now it’s just a playground for my ideas and that suits me really. I carry around everywhere so it’s ready to be used.
I wrap my latest notebook in a Coal Creek leather cover to look all fancy (and hold my phone and pen). https://www.coalcreekleather.com/collections/a5