One of the things I have to do often is discovery work. Breaking down a process to understand how it really works, it's strengths and weaknesses, and then define how it can be improved. OneNote has become an invaluable tool in that effort. When I'm working on breaking down a flowchart for a business process, I'll go through three steps to make it easier to capture the information I need about the various parts of the chart.
Step 1 - Create pages for each section
I use the screen capture in OneNote or Nimbus in Google Chrome to capture screen clippings of the various parts of the flowchart I need to break down in detail. By pasting the screen clippings onto individual pages in OneNote, I can focus on the details of that section without going down the rabbit hole of the entire process.
Step 2 - Side by side documentation
Since OneNote allows for text boxes to be placed in various spots around a page, I can easily drop a text box next to the screen clipping and capture the notes about the section in context to the image. If I need multiple sections, say for example I find several items needing follow up, I can just press Ctrl-1 to add a To Do tag to the item for later.
Step 3 - Tagging important items
As I go through the process analysis, critical items such as data fields that need to be captured come out in the discussion. I use the important tag (Ctrl-2) to mark those items for later. Once done, all I need do is search my notebook for all important tags and I have a quick list of all the data columns that need to be created.
Scratching the surface of OneNote
OneNote has become an invaluable tool in my work and these steps just scratch the surface of the number of things that can be done. Coupling this with systems such as SharePoint Online and the process of process improvement got much more efficient for me.