Staging a Wordpress based website means, that you use all of the well known three stages in your Website environment:
Staging is the process to promote a snapshot of the development version (revision) from staging (testing for production) to the production website (release).
The Staging step is used to not run development code directly on a production site. In difference to the standard release cycle (development, beta-testing, release) Staging is something that a developer can do all the time. So the development version can be a stable wordpress release but extended with own plugins or themes for example.
This section is a placeholder to describe how to move a website from one host to another. This for defining a process.