Beginning with JavaFX

I have started to learn Swing and almost completed. I think tending to JavaFX for desktop GUIs. Where should I start? I have looked up some oracle pages but I've not found expecting result that most of them are related to web applications. The other question is should I use always hand-writing while developing gui? If not when should I use form layout managers? Besides, if there are books about desktop applications with JavaFX, feel free to share.

Here (on the left side) is a good place to begin.  There are two main ways to build a JavaFX app: with FXML or programmatically.  The latter is more like Swing.  You create GUI components in the code.  With the former, you build FXML files that describe the GUI components.  You can write the FXML by hand but most people use SceneBuilder.  Although the source code for SceneBuilder is provided by Oracle, strangely, they don't provide the executable.  That's why the link is to Gluon.

I would try a simple GUI with code only first to get the hang of JavaFX.  If you want to look at a project that uses JavaFX in code, look here.  I have started a project using SceneBuilder and FXML, but it is not finished.