You can use a storyboard, for sure, but some of us have difficulty translating images of stick  figures into the full Technicolor images we need to see in our minds.

One concept is to visualize all the scenes in your story as a set of images from a movie. Isn't that how we normally tell a story anyway?

When we relate an anecdote to a friend about what happened at the grocery store, we first SEE the sequence of events in our heads. We can recall the expression on that lady's face when we ran into her cart. We can see the look in her eyes, and hear the tone in her voice. Sometimes, we can even imagine what the background music might be as the scene progresses. 

We string these images (some still, some actually moving) together to make the whole story. Sometimes we stay in the role of the narrator, sometimes we play out all the characters in the scenes. Either way, we see it as a movie going on in the projector of our minds, then we describe to the listeners what we see on our screen.

Don't memorize the words, memorize the images, and remember the scenes from the movie.