Clone the folder and then install the extension:
Bring up the extensions management page by clicking the wrench icon and choosing Tools
> Extensions
.
If Developer mode has a +
by it, click the +
to add developer information to the page. The +
changes to a -
, and more buttons and information appear.
Click the Load unpacked extension
button. A file dialog appears. In the file dialog, navigate to your extension's folder and click OK
.