1. Read more. Set a goal for a number of books a week, a month, all year.
2. Write more. Set a schedule or resolve to write X many hours or words a day, week or month. Vow to finish a first draft, a revision, or X number of short stories. Maybe you do your writing on a blog, set a schedule to post weekly or biweekly.
3. Share more. Join a critique group to share your work and help others as well. Read pages at open mike night. Send queries to agents or editors. Attend conferences. Get the word out more about what you are doing.
4. Learn more about the craft. Take a class in writing or read a book about craft. Some good books that will make you look at the meat in your stories include, "Writing the Breakout Novel" by Donald Maass and "Save the Cat" by Blake Snyder.
5. Experience more. New experiences and observations are the heart of creativity. Don't be afraid to explore, try something new, attempt another form of art, stretch yourself.