These instructions are the same for PC and Mac.
From within your OpenOffice file, go to File > Export as PDF.
- On the General tab select either Lossless compression or JPEG compression with a Quality of 100%.
- Reduce image resolution to 300 dpi.
- Select PDF/A-1.
On the Initial View tab select Page only.
Select Default for both Magnification and Page Layout.
- On the User Interface tab deselect everything EXCEPT All bookmark levels.
On the Links tab deselect everything EXCEPT Default mode under Cross-Document links.
On the Security tab do not select any options.