TL;DR: I plan and it helps me.

When I'm working in IC mode:

- I plan for the next day at the end of the day (org-mode).

- If I'm working on planned tasks (programming, demoing, documentation, etc.) I tick checkboxes. These tasks are usually small enough to do in 1-2 hours.

- I also tick checkboxes for must do things e.g. when on call.

I'm sceptical about planning and working on a bunch of things without putting them down.