This may seem a little circular, but people often have unfounded fears or unfortunate preconceptions about disability. The only thing I have seen that works every time is to have real live people with disabilities, doing meaningful work, just like anybody else. Things can be a little awkward at first (tip: a little etiquette training helps) but eventually it's the person who is seen, not the disability.
When you reach that point, accessibility awareness becomes personal. It's not some hypothetical person, it's Susan who can't hear the training video or Joe who can't read the PDF.
And when it's personal, it's a lot harder to hang onto fears and misconceptions.