Visual recording is similar to audio recording: they both use the same concept that is : recording. One uses voice and the other uses visual cues like diagrams, charts, lines, arrows...etc. Think about visual recording as visual mind mapping.
Visual recording using your iPad is something you can best do via the help of some powerful apps. The video below will walk you through the process of how to capture your ideas visually on your iPad. It will also show you how to use each of the four apps suggested. These apps are :