Teaching listening

I think that teaching listening would be the hardest thing for me to do. I think that is harder than it might seem.In fact,  I am trying to improve my listening skills because sometimes I just don' t understand what English native speakers are talking about. I have been thinking on the concept of using both bottom-up and top down listening techniques when teaching English.Students who are just beginners, would not be able to understand whole sentences.For example, when listening a story,  I think that I would ask them to listen for key words already explained.Now, I am thinking  how could I explain those key words to kindergarten kids If I had to teach them.