If you are a newbie for the WAS Liberty Profile Server,you can watch the below video to learn about it.
The whole installation is very simple. Open the Eclipse，Click Help > Eclipse MarketPlace，in the search bar enter liberty and click search,then click install button.
You can create liberty server through server-->Server Run time Environment,add WebSphere Liberty Profile to install runtime environment.
There are two ways to install
1. Visit wasdev.net site，download Liberty 的installation files，Liberty installation size is less 50M，unzip your installation package to one specified path,then point to the specified path as your run time enviorment path.
2. Follow above screenshot Download or install link，you need to online download a liberty server environment
When you finish the configuration,you should see the liberty server in the below screenshot.
Double Click the Server Configuration，You can see the server.xml.It is the core part of the liberty.All your configuration is through this file.
<server description="new server">
<!-- Enable features -->
You can also use GUI to config this file.
The default config only support jsp feature,you can add more features to support.
Open your liberty installation folder <Liberty_Install_dir>\usr\servers\server_name,you can see below structure.The application configuration files will be default put under apps folder.Also you can directly put the war files into the dropins folder,when start the liberty server,it will scan these two folder and automatic start the application from these two folders.
If you want to learn more detail info about how to develop the application on was liberty,I suggest you to read WebSphere Application Server Liberty Profile Guide for developers