The best way to understand something is by doing it or thoroughly "understanding" it.
Associating a concept with an example or an analogy is the best way to understand. I like the ADEPT method of understanding a concept. It is difficult to come up with an analogy for everything but it does work for most of the cases.
A picture helps store and a recall the information quickly when needed. The words are always associated with an image in our memory. Images also have a longer recall value.
I often condense a full book's worth of information in a single visual. My visuals help understand the concept at a level 1. You do need level 2 and 3 and so on to understand the concept in more details as needed. But often books dive into details quickly which takes a lot of time to consume and does not have a high recall value as there is no association of the information with a picture.
As an example, I try to explain a very high level working of capital markets. The picture touches on many different things like stocks, bonds, demand, equity, debt, etc...For a non-financial person it would be very helpful to first see this visual and then try to understand the concepts of the capital markets. The visual gets etched in memory and has a much higher recall value when needed.