When I first tackled React, I went through all the best tutorials available online. Joe Maddalone from Egghead, Tyler McGinnis' introductory course on React, the Code School course, even a few PluralSight tutorials. Although these all gave me an excellent working knowledge, nothing really made it click until I took on a project and forced myself to craft a React-based solution.
As I'm used to static CSS/HTML with jQuery/JS to manipulate the DOM for simpler portfolio sites, writing the app in React from the onset required me to answer common use-case questions from its perspective.
"How do I add CSS styling once a user scrolls?"
"How do I add local images?"
"How do I hide/show this?"
What resulted was a new appreciation for the workflow, as well as a revision to the way I approached building a page in the first place. It's one thing to understand all the inner workings and best strategies for the library; knowing how to use it as a tool is best learned from rolling up your sleeves and pushing through it!