...
At this point, you have either installed the standalone Design Studio or installed the Design Studio plug-in into Eclipse. If you have already done so, you should also install and run the Pentaho BI Server and test the samples in samplesbi-developers/getting-started to insure your BI Server is functional. Also try one or two reports in samples/steel-wheels/reports within your environment and with your browser. For more information about installing and configuring the Pentaho BI Server refer to Getting Started with the BI Platform
...
You should now see your Pentaho Solutions project displayed in the tree on the left side of the Design Studio. If you expand the solution folder you'll see plenty of files. These are the files that make up your solution and are managed within the Design Studio. Let's take a look at one to get a feel of what the Design Studio can do for us. Go ahead and in the left hand tree, open the Pentaho Solutions/samplesbi-developers/getting-started folder. Double-click on the HelloWorld.xaction file and the Action Sequence editor will open in the edit pane.
...