When you open Spirit Studio for the first time, you will be prompted to log in. You need a valid Spirit subscription in order to proceed. Enter the registered email address and activation number (check your mailbox).
Once the application is started, you can connect to any web page by clicking on the browser extension in Chrome.
All animations on the Spirit homepage are created with Spirit Studio and can be altered. This is a good starting point to fiddle around with the animations and see how they're created.