Installation

The most recent OLy version can always be found at the top of the Download page. (You can also look at the Releases page.)

In LibreOffice,

open the extension manager (Tools -> Extension Manager),
click the "Add" button which will open a file dialog,
select the *.oxt file you've just downloaded,
confirm with the "Open" button.
When asked for whom you want to install the extension, you can choose "only for me" which won't require administrator privileges on your system.
After successful installing, close the extension manager.
Probably you will now be requested to restart LibreOffice.

After restarting, LibreOffice will have a new "OLy" toolbar in Writer, Draw and Impress. It contains an "OLy" button that launches the extension.
(The "Batch" button will only appear in Writer. It is discussed in a later chapter: Advanced features - Batch processing)