The more you write, the more you can write.
The more you think about writing, the more ideas you have.
The more you look for opportunities to get your writing out there, the more opportunities you find.
Yesterday I found a local short story competition whose closing date is next week. I found it in a magazine I would never normally pick up, in the doctor’s waiting room. I had a story already written which I could use, from a time when I was writing more than I have been recently.
It spurred me on, not only to enter the competition, but also to write more stories, so I have more to choose from next time opportunity comes knocking.