I would add the importance of surrounding yourself with images by others. Especially images that you respond to. Go to galleries, go to the library, browse magazines. There are elements of "good" images that are common to many and crucial to most. As your level of seeing improves, the images you pass up will increase, and the ones you go after (possessing the tools to do so) will start to approach your ideals.
The only thing you can take a picture of is light. Make sure it's good light!

"Omnia lvmen divisvm in partes decem est"