Great things about being blind, Entering and leaving a room.

So, you enter a room where I am.  Unless it is very quiet and I heard you open the door or walk in, I might not know that you came in, who you are, where you are in the room.  So, when you enter a room and if you know I am there and am blind, say something.  You could just say something natural like hello.  If I know your voice, you don't need to say who you are.  I'll ask if I don't remember.  If we've never met, it would be helpful if you say who you are and if anyone is with you.  And, if you  have to leave our conversation to go somewhere else within a crowded room, could you tell me first?  I've had many conversations with walls, posts, or other objects when I thought someone was still standing there talking to me.