Spend as many hours a day reading as you can. What you read doesn't matter as much the fact that you are reading. Broaden your literary horizons as much as possible. If you have read all of William Faulkner's novels and short stories, for instance, track down Thomas Mann's "The Magic Mountain" or James Joyce's "Ulysses" before picking up another example of Southern Gothic fiction by Flannery O'Connor or Carson McCullers.
Practice writing even when you don't feel inspired. Sometimes you just have to stare down the blank screen and make yourself get to work no matter what you have on your mind. Eliminate distractions in your writing environment. If you write on the computer, close your Internet browser and other applications.
Apply to Masters of Fine Arts programs in the genre of your choice (usually either fiction, poetry or creative non-fiction). While these programs often prove expensive, they can earn you valuable contacts in the academic world that can eventually lead to teaching appointments at colleges and universities.
Look for internship opportunities at publishing houses. Anything new you can learn about the world of publishing can help you to break in yourself in the future.
Write to your favorite author asking for advice. While no guarantee exists that he will answer you, you never know. He may just have something helpful to share with you. Check with his publisher for contact information.
Come up with a personal writing quota for yourself. Decide whether you want a daily, weekly, monthly or even yearly quota. Choose whatever fits your needs and ambitions as a writer. If you are a beginner, just trying to write 1000 words a day can be a huge challenge. On the other hand, many professional authors write upwards of 2000 words daily.