What you need to know to interact, communicate with and understand(relate to) a vision impaired/blind person during a conversation.
This is an article with personal information learned from experience living with vision loss for twelve years after, losing my vision at age forty. A person born without vision may or may not experience the same difficulties.

Before beginning to understand a vision impaired person you need to put yourself in the shoes of a vision impaired/blind person. A good way to do this is using a pair of sleep shades, blindfold or simply closing your eyes (hint: must be willing to keep eyes closed at all times or doesn’t work). Next, try doing these ordinary tasks.

A) Sit in your living room and listen to the sounds around you.
Try to identify what you hear. Ask your spouse or a friend to make some sounds and see how many you can identify. Think about a blind person using only hearing or a scent to identify what he or she is hearing. Notice how difficult matching a sound with an action is when you receive no information from your eyes.

B) Sit and have a spouse or friend place different items near you and try to identify the item using only the scent of the item.
Try identifying ten items using smell only – see if you can get five out of ten correct. Pay attention to the difficulty of identifying items using only the scent of the item.

C) Sit and talk to your spouse or a friend for a ten-minute conversation.
After the conversation, review how you felt talking to someone without your vision. Pay attention to the difficulty you experience if any, following the flow of the conversation. Did you find yourself guessing when it was your time to respond without a pause or interrupting? Did you have difficulty staying interested in the topic of conversation? Emotionally how well did you relate to the other person? A visually impaired person does not observe the emotional language the body can express and depends on sound and word expressions.
Humans use the eyes to gather information more than any other body part. A blind person does not have the vision advantage. Therefore, information gathered from watching body movements such as the eyes, hands, feet, head and overall body parts while talking is not available. A person’s facial expressions and believe it or not the eyes(direction the person is looking while talking) can effect the way you respond to what a person is saying. If a person rolls the eyes while you are talking, that action can affect the way you speak to the person. A blind person instead relies on your exact words, the tone of your voice, the accent you put on a word(s). The volume of your voice and the sounds you make while talking to help understand you and your emotions while talking. Listening becomes a very important skill. The saying, “read between the lines” takes on a new meaning for the vision impaired.

During my training and education, I was instructed on techniques of interacting with a sighted person when carrying on a conversation. The most important tip was “always look in the direction of the person who is talking to you.”

After several years of practice, I still have lots of work to do on my listening and communication skills as a blind person.