Probably in the same way as this site handles pictures. You need to host the documents somewhere, using your own web server or on one of the many free sites. Then, you just post a link to the document.
I recently posted to Here
Copied from PDF file, you need to choose the correct 'tool' for selection of text or image .. copy to clipboard ... open, for example, M$ Photo Editor .... 'Edit' 'Paste as new image' save that image as JPG file then upload to perhaps http://imagehost.darkernet.co.uk/index.php max size allowed 100KB ! Note the address given after uploading complete.
Then post a link hereabouts to that address.
Experiment with sizes etc using 'Preview'
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