Create a space for writing and write there every day. By developing a practice of writing, in the same place at the same time, you will begin to build your defenses against writer's block and distractions.
Schedule your writing time like any other appointment. Start with just 30 minutes daily. Once you can comfortably write for 30 minutes, move up to an hour.
Write whatever you are thinking about, even if you don't think you have anything to say. Slowly your voice and vision will begin to emerge: Ideas will form and, once formed, become characters, then plots.
Give yourself permission to write terribly. Editing comes later. For now, what is most important is getting your ideas on paper.
Take a class. Community colleges, universities and writing organizations offer classes in a variety of genres, where you can get feedback on your work from fellow students as well as an instructor. Many courses can be taken online, or during evenings or weekends.
Join the online community. Forums, message boards and groups on professional sites like LinkedIn offer an opportunity to network with other writers. You can read about their day-to-day struggles and successes and find out about competitions, readings or other chances to get your work in the hands of editors and the public.
Find a writers group to provide encouragement, critique and, most importantly, deadlines. You will give and receive feedback, getting honest opinions about how your work comes across. Unlike a class, a writers group has no instructor or assignments: Each writer brings whatever he is working on.
Enter competitions. Many trade and literary magazines have annual or quarterly competitions. The winners are usually published in either the print or web version of the publication. The entries are usually anonymous, so anyone can win.
Donate your writing. Write reviews of local businesses on websites like Yelp or post book reviews on Goodreads. Offer to create blog posts for a local business. This may seem like "free" work, but it is a way to make connections and get noticed. It also begins to build your writing portfolio.
Find a paying audience. Every year, "Writer's Market" publishes guidelines for thousands of publications, from periodicals to book publishers (see Resources). Trade publications such as "Poets and Writers" magazine list regular calls for submissions.