I'm pretty sure that the best way to get a toehold in writing is to start writing work that you yourself want to read. Then, see who really cares about it, and try to understand why.
(Quote: Sterling himself.)
Vajra got started for precisely this reason. I had a kind of story I wanted to read, and I couldn't for the life of me find anything remotely like it. So, I went and wrote it. It remains to be seen if I scratched anyone else's itch at the same time, though.
The hard part about doing such a thing, of course, is not ending up being a slave to a passion that only you and absolutely no one else can connect with. That's part of why writers are always encouraged to remember the fundamentals: tell a story with a beginning, middle, and end; use the language that fits the material; don't leave the reader behind; every piece of work exists only because there's an audience for it that isn't the writer; and so on.
The other half of this is knowing what you yourself want to read that's truly yours. One of the things I had to discover on my own was how everything I encountered that I liked wasn't the outside limit of what was possible. There is no "greatest" of anything, or "last word" in any creative endeavor (although there ought to be a canon), because life always continues in all directions, and new things are always crying out to be said in light of that. I spent years struggling with my feelings of jealousy for works I admired, before learning how to convert that into lessons learned and not simply blind emulation.
But caveats aside, there's little question in my mind that the most vitally creative work is produced by those who are seeing something, however small, that absolutely no one else can see first.