There is much to be said and learned about the art of listening and responding. Most recently I watched a charming TED talk by Celeste Headlee entitled "10 Ways to have a Better Conversation." The big take away is that she emphasized that everything you have learned about "showing" you are listening is wrong. Her main point? You don't have to show you are doing it if you are doing it. You don't have to pretend if you are.
There is a manner of authenticity and respect for the present moment that I think should be highlighted here. It really is reminiscent of that famous quote of Yoda's from Star Wars, remember it?
"Do. Or do not. There is no try."
Someone might argue that Yoda was a Jedi Master so easier said than done, but I am not not a Jedi Master (yet) and I would argue back and say its easier done than said.
In role playing scenarios and improvs the thing to always focus on is not what you are going to say or want to say next, but instead the focus must be on your partner. To continue with our Jedi analogy let's think of The Force. The most important thing Luke Skywalker has to do is concentrate, take his energy and put his focus outward. When he is able to achieve that he is able to move mountains. (well, spaceships)
To be sincere listeners we must hear what the speaker is saying, what they are contributing. All else follows from there. Your goal is not to plot, plan, or problem solve, it is to respond. Repondez s'il vous plait.