What you need to understand and try these samples:

• an IDE
• Websphere Liberty about page
• Java JDK 1.8 Oracle Java downloads

What I used:

• eclipse (I used "Eclipse IDE for Java EE Developers", Mars.1)
• in eclipse I installed the WDT (Websphere Developer Tools)
  • via marketplace (search for "IBM WebSphere Application Server Liberty Developer Tools")
  • or use this link: marketplace-link
  • source of marketplace link
  • marketplace web link
• to prepare the eclipse / workspace you should add a liberty server
  • File -> New -> Server -> server type "Websphere Application Server Liberty" -> Next -> choose "Install from an archive or a repository" -> Next -> enter a path where you want the server to be installed & choose "Download and instal..." and there the "WAS Liberty V8.5.5.8 with Java EE 7 Full Platform" (yeah, it's a very long name...) -> Next -> (No Additional Content needed) -> Next -> Accept license -> Finish
• start the server (in the Server-Tab), and you must add a keystore password. (for these example not important. it adds a line to the server.xml)

Just to have a look a the projects:

• Import the projects from the repository into your workspace
• Define a run configuration for each project
  • for the 'HelloEJBSample' set "install" as the goal
  • for the 'HelloWorld' & 'HelloEJBSampleTest' set "clean test" as the goal
• run the 'HelloEJBSample' first to install the artefact for the 'HelloEJBSampleTest'-project
• stop the liberty server
• run the tests

How I built each project

'HelloWorld'

• create new simple maven project
• writing some code that is to be tested (I used the example from this tutorial: https://developer.ibm.com/wasdev/docs/getting-started-liberty-arquillian/)
• now the class "HelloWorldServlet" and the spring bean "SpringBean.xml" exists

[to be continued]