As a writer you need to remain alert for opportunities.
When picking up a magazine or paper, not only look at the contents but consider ways you could possibly contribute.
Is there an article on a subject that particularly interests and which you could develop or expand on? And importantly, is there something missing from the magazine or paper which you could contribute?
By adopting this approach and keeping alert for writing opportunities you will see openings and, in time, some can lead on to acceptances.