Look up your market website or at their submission policy, usually found on the index page.
Go to their "Submissions Manager Page."
Poetry Magazine (https://submissions.poetrymagazine.org)
Loaded Bicycle (http://www.loadedbicycle.com/submissions.html)
Set up a manager account. (They are free.)
Submit your poem.
Most of them take one to five poems per submission.
Most magazines out there, both paper and internet, use the submission manager. You can go back and check, or wait until they email you.
For short stories, if you have a paper magazine, look in the small print at the beginning of the magazine for submission policy, or go to their Website.
It is a good idea to go to your market and read what they publish to understand the market.
I have not found anyone willing to steal my work. The Science Fiction Writers of America, Mystery Writers of America, Critters.Org, an other places track magazines and markets that do these things.
I just sold a short story to an internet Halloween Anthology, (Whortleberry Press). Their submission guidelines list what they want and how the want it sent.
I just submitted a story to New Yorker, and expect a rejection in three months. They are the most prestigious magazine out there.
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