Export page size of PDFs

I’m wondering if someone could explain how to change the page size of a pdf and/or ODF export. Most of the exports will never be printed so removing the default 8.5x11 will help with the table and image cutoff on the right. Even the ability to change the orientation would be better and ensure things are not running off the page. I’ve hunted for the answer as a non-developer and not found a clear answer. Maybe someone who is expert can throw this SA a bone :wink:
Cheers and thanks in advanced.