As Jim Hatch and others have said, the important thing is publishing your pattern in a magazine. I would later also publish it here on FAOL but it is nice to have something with your fly in it that you can hold in your hand. The problem of course is getting it published as an article. Many magazines are backlogged into the next year. You may find it rejected simply because a very similar fly had just been published. You can of course send it to places where just the fly and recipe are published, but an entire article is really nicer.
I often see articles published claiming to be new and original. For instance I have seen at least 5 articles on the
hackle or wood duck, or other feather wing where one side has been stripped and the stem pulled over. The earliest was in the late 70's. Minor differences perhaps but not enough..some simply pluck a few barb out intermittently to give less air resistance.
What often happens when you sell a pattern to Orvis, Umpqua, or Spirit River is that you will soon see the same fly under a different name. That is what happened to Tom Baltz and his "I can See it Midge."
Don't forget, they often blow pictures up and the slightest flaw will stick out like a fake pine tree cell tower. Use a good camera and a light color (not white) background behind the fly. Good luck and let us know what you come up with... Bob