“Always be sure you get your moon in the right part of the sky.” — Herschel Brickell
Research. Do it. No arguments.
Seriously, does it drive anyone else nuts to be reading about something you know a little (or a lot) about and have it proved abundantly clear that the writer has done no research into the topic, figuring they can “slide by?” It’s pure laziness, particularly in this age of instant information. And sure as God made little green apples, SOMEONE out there will read your stuff and call you on it. Not face to face, perhaps, but all you need is one reader telling another “This writer doesn’t know what s/he’s talking about” and your validity is shot. Take the time to research. Take the time to care. Ask questions. It’s amazing how many pros in a field are more than willing to talk about what it is they do, and they’ll take a little time to do it. (And if you’re meeting them face-to-face, offer to buy them lunch or coffee. And make sure you acknowledge them in your book/story — even if you DON’T end up using the information. They were still willing to talk to you, and that means a lot.)
This also ties in to training yourself to be a good line editor and finding (if you’re lucky) someone to cast an additional eye onto your work. It’s amazing what someone can catch that you’ve missed. I know I experience becoming “too close” to the story — I’m intimately involved with the characters over a long period of time so I inherently “know” everything and sometimes read more into the manuscript than what I’ve actually written, forgetting that others don’t know as much as I do about it. This is where a good editor/proofreader becomes invaluable. (I remember back in high school, when I used to write stories with friends, having one of them point out to me that a particular character’s hair and eye color had changed from page to page! And I never noticed it because I was so caught up in the process.)
Take time. Care about what it is you do.