Being in the Moment
Between composition and technique, there can be a lot of things to think about when you're out shooting. But especially when the shooting gets good, there's often not a lot of time to stop and think. You really need to be able to just go with the flow of what is happening and react to what is around you to get the best shots. Otherwise those magical fleeting moments we all strive to witness may just pass you by.
Before you go out, spend some time looking at other peoples work because you enjoy looking at great photos and you'll never know where you'll find them. When you find one you like, ask yourself why you like it; when you find one you don't like, ask yourself why you don't like it. Read books on composition (as many different ones as you can) to gain different perspectives. Learn good technique (how to operate your camera, exposure, and so on) so that it becomes second nature.
But when you go out shooting, there should be only one thing on your mind: "this is fun!" So long as you're worried about "being original" or "having your own style" or "how do I figure out what the proper exposure for this shot is" or anything else, this will get in your way. Don't worry if it's original, or if you have your own "style." Simply take pictures because you love doing so and the rest will work itself out.
Everything you do before going out to shoot is preparation just like the musician does when he prepares by practicing his scales and studying music theory, or by listening to other peoples work to gain an appreciation for what is possible. When a musician goes out on stage, though, he does none of that — he plays.