I think the most important skill for any filmmaker to have is the ability to visualize a movie. When thinking of a scene, make sure to think about camera shots, sound, where the character stands and says, and maybe even music. Then try to play the movie in your head so now the characters are moving, talking, and the camera shots are also changing in different positions(CUTS). Never done this before? Think of a ball. Now ask yourself, what color was the ball? Size? Type? Where was it? You should have a picture in your head. Now with out moving the camera, make something move within the shot. Maybe a kid comes in the picture and kicks the ball out of the picture. Include sound effects. If outside, is there birds, other people? I think visualizing a existing movie is kinda cheating. Try to make up your own scenes.