Lot's of great advice here, especially around listening. It's hard to do, as it is hard to even recognize what it really means, especially when you are not doing it well.

A big learning for me was how important humility is in communicating well.

For me, How to Win Friends and Influence People made me realize that. The title may be a bit offputting, but I found the book to be the catalyst that led to a lot of positive self-change. It shone a light on things that I have not been great at. The book did it in a way that did not make me defensive, and allowed the message to hit where it was needed. In a way, that is a demonstration of what communicating effectively is.

I put off reading the book for far too long, as I heard many summaries of it. The summaries don't do it justice.