I never took a communications class (one crappy public speaking
  course I think) but I'm naturally empathetic so when I find
  people aren't understanding me, I try to think about them. How
  might they be receiving me? How can I keep my message but change
  the presentation in such a way that they will be able to accept
  what I have to say more readily? So, I may have to explain
  myself 12 different ways, presenting various analogies and
  metaphors. The better I get to know someone, the easier it
  becomes. I have a "come with me on this journey" attitude when I
  write. I envision the person sitting next to me and we're going
  on a ride together, facing the same way. I don't know why, but
  it seems to help communication for me. I'm using it now. Unless
  someone gets me really really mad, it's a habit and it's
  effective. I don't know if it works for everybody - we're all
  different... but it does for me.