This article will briefly walk you through the steps to export an image from Earth OnDemand into QGIS.  After querying the Earth OnDemand catalog the images that meet your selection criteria are shown on the left hand side.  Select any image you wish and click the Link button.  This will produce a small pop-up window.  Then select QGIS Tile Layer.  Another pop-up window appears with a QGIS Tile Layer link.  Click the Copy button.

Now you can open QGIS on your machine.  Once in QGIS look for the browser panel, which is usually on the left hand side of your QGIS workspace.  If you don't see it select View from the selections at the top.  From the drop down menu select Panels then Browser.  Now a Browser panel should appear on the left hand side. 

In the Browser panel find XYZ Tiles and right-click it.  Select New Connection and an XYZ Connection window pops up.  You can now give the connection a name and paste the very long URL copied from Earth OnDemand into the box labeled URL. Finally, click OK at the bottom to close the window.

Now if you expand the XYZ Tiles in the Browser panel your Earth OnDemand image should be listed with the name you provided.  First, it may be helpful to add a base layer to your project if one is not there, such as OpenStreetMap.  Now go back to your image name, right-click it, and select Add Layer to Project.  Now your image is available as a Layer in your QGIS project.