1. Turn your Kindle on.
2. Connect the Kindle to your computer using the USB cable that came with your Kindle.
3. Drag and drop the ".mobi" ebooklet file into the documents folder on your Kindle.
4. When the USB activity indicator on your Kindle stops flashing, "Safely Remove Mass Storage Device" (Windows) or "Eject" (Mac) the Kindle from your computer.
5. When the USB activity indicator on your Kindle stops flashing, unplug the USB cable from your Kindle.
6. The ebooklet should now appear in your Kindle library.