If Scratch is not already installed, click here to get the instructions from the Bird Brain Hummingbird Kit website.
Plug in the Hummingbird, then launch the Hummingbird Connection App from your Apps launcher page. The following window should appear:
Click the Open Scratch button on the app to automatically load a ScratchX page with the Hummingbird blocks loaded. Click Enable Flash if needed.
If the ScratchX interface with Hummingbird blocks doesn't load, click Open Extension URLand then enter the URL for the Hummingbird:
http://birdbraintechnologies.github.io/Chrome-Scratch-and-Snap-Support/Scratch%20Plugins/HummingbirdHID_Scratch(Chrome%20Plugin).js
Attach the power source to the Hummingbird kit and plug in.
Connect the USB port to the Hummingbird and to your device.