I use paper a lot, but no notebook. What I find disturbing with them is the mixing of different projects stuff. Also I prefer to have a lot of space for drawing

I use paper a lot, but no notebook. What I find disturbing with them is the mixing of different projects stuff. Also I prefer to have a lot of space for drawing. That's why I use blank gridded A4 paper sheet. Then I put together project related notes. If a project starts to be big enough, it will naturally lead to a pack of papers that I can carry along. Otherwise the project can kind of fade away be laying around or being mixed with other sheets. I mainly draw application architecture and app screens. I also tend to note in natural language problem related to those. So this is design notes. For technical notes about deployment for example, I use One Note.