LibreOffice Writer: Make the odt file size smaller: Export it as PDF

- Open an odt LibreOffice Writer odt file
- Menu > File > Export as PDF
- Click on General tab
- Under Images, tick “Reduce image resolution” checkbox and set it to 150 DPI
- Under General, tick only one checkbox which is the “Export bookmarks”. The rest of the checkboxes should not be ticked
- Click on the Export button
- Done