One of the things that can scare nascent writers about science fiction is, well, the science. Even professional SF/F writers, like my mentor Eleanor Arnason, have been known to choke when it comes to the nuts and bolts part of the story.
First of all, don’t let "getting it right" stop you. Remember – William Gibson wrote his groundbreaking cyberpunk novel Nueromancer on a typewriter, and while having almost no experience with a computer. All you really need from the science is the spark for the idea.
In fact, a quick side story about all of that.... I had the honor of being at the pre-award banquet for the Hugo the year that Eleanor's "Stellar Harvest" was nominated in the novelette category. She had named me her alternate, because she didn't want to deal with going to the award ceremony. I talked her into going. Which was funny in and of itself since my name was listed on the guest list and on the reserved chairs, and I actually had to tell the guards at the door that Eleanor was _my_ guest.
At any rate, being the sort of person I am, I instantly recognized all the luminaries in the room (I regularly scan the photos of LOCUS so I’m never caught with my pants down, as it were.) At any rate, the editor of Analog came up to Eleanor in a kind of fanboy way and started telling her how much he loved her work. I could see her slinking away from him, so I took on the role of introducer, even though he and I have never met. I said, "Eleanor, do you know Dr. Stanley Schmitt?" She brightened instantly. He immediately chided her for not sending more of her stories his way. She gave a dismissive wave of her hand and said, "My stories aren't technical enough for you." Dr. Schmitt never missed a beat. "Eleanor," he said, "Let me be the judge of that."
The point of this story is that the story elements -- like character and plot and theme -- are far more important to most editors than the preciseness of the physics (or chemistry or biology or math). Now, that’s not to say you have a license to not TRY to get the science as right as possible, because SF/F fans (your readers) will notice egregious errors and be more than happy to corner you at a convention and explain the way gravitational physics REALLY works.
I think the key to writing successful science fiction stories is to be enthusiastic about the science you're writing about. I don't think about science every day, though I'd like to. One of the ways I keep myself open and receptive to the seed of a science fiction story is to hang out where ideas germinate.
If you're struggling to find SF ideas, (or if, like me, you just like to hang out where the smart people are,) I'm going to suggest that after you read the New York Times in the morning (or whatever your post-coffee gathering ritual is) you check out some scientific web sites – or, like I do, keep a few of these magazines in their print form in the bathroom for quick perusal.
Popular Science
Popular Mechanics
National Geographic
Science News
There are many, many more I could list, but the articles in these magazines are written in such a way to make you the kind of vaguely informed dangerous that really promotes a good science fiction idea. That's to say, they aren't terribly technical and they leave out the details that would probably send your idea down in a flaming wreck.
Half-assed ideas are the ones with the most wriggle room. Go for it. Make your characters real and the situation believable and the science won’t matter. Get it close enough, and then find an expert to fix what needs fixing. Or just pray that with enough hand waving, the editor will be so charmed by your work that s/he won’t give a crap that your science is wonky.
Next up -- Part III: The Magical Forests of Schenectady, or Hunting Down and Capturing Fantasy Ideas
