Activate the theme
Go to WP-admin -> Appearance -> Themes as seen on the screenshot and click the "Activate" button.
You will now be walked through the One Click Installation process. Just keep pressing Next Step button and then Finish it.
In the next step you can have a look at your site.
If you now open your site on the front end, you can see the barebones of the theme. For your convenience we have already filled it with some content, but you should learn how to add the rest of the content later in this Documentation.