When you're a kid with a guitar, the instrument hardly ever leaves your hands. Then you buy a four-track and make your first recording, and that's when you learn a hard lesson: No matter how many hours you've spent playing unplugged, your whole world changes once that red light clicks on.
You can't practice for recording. You can only record. It's the same with playing in front of an audience -- and it's the same with writing. If you want to be a writer, it's not enough to write; you've got to publish. Start a blog. Write reviews on Amazon. Mail a letter to a local newspaper. The point is, that psychological component is absolutely essential: You need the threat of an audience.