Be relaxed in your dealings with people with disabilities. If you are relaxed and act in a friendly and caring fashion you put the person at ease and contribute to a more comfortable and relaxed ride for the passenger. Be yourself. Never shout at people if you think they can't understand or can't hear, this makes communication harder. Always speak clearly and distinctly
If a person is hard to understand be patient and listen. Don't assume you know what they will say. Don't interject, cut in or finish sentences for them.
Show common courtesy at all times. This includes not moving into people's personal space unless invited Don't "hover" over passengers with disabilities. They do not wish to be treated as children.