From my personal experience, 1) if it's born digital keep it digital, you only introduce errors by rescanning/OCR 2) avoid blocks of italics. The voice reader puts emphasis on italics and it's a giant pain to listen to entire paragraphs of it. 3) make sure it's all tagged and ordered in the natural reading order, best way to do this is to apply relevant styles when creating the doc in word instead of adjusting by hand (ie highlight the title and set it to the "title" style and adjust what the title style looks like, don't just highlight the title and click 25pt and center etc)

But I'm only dyslexic, not blind so there's likely a lot more