Barnabas Piper offers the one key component to good writing: playing baseball. (Double-check me on that.)
On that topic, Stephen King says in his widely praised book On Writing, “If you want to be a writer, you must do two things above all others: read a lot and write a lot. . . . If you don’t have the time to read, you don’t have the time (or the tools) to write.”
He also says, “Description is what makes the reader a sensory participant in the story. Good description is a learned skill, one of the prime reasons why you cannot succeed unless you read a lot and write a lot. It’s not just a question of how-to, you see; it’s also a question of how much to. Reading will help you answer how much, and only reams of writing will help you with the how. You can learn only by doing.”