- Carefully do the official [tutorial][].
- Read the official guide to [main concepts][].
- Read the official [advanced guides][].
- Watch [building React from scratch][] to get an idea of how React actually works (this covers the "stack" reconciler which was used in React 15 and earlier).
- Go through the [React "fiber" architecture][] which is the default reconciler since React 16.
- Go crazy, build your own projects, and stop doing React tutorials!