Interviewing is a Perishable Skill
Just stop for a second, first, and realize that I'm not advocating for job-hopping. I also don't want to come across as suggesting that you waste other people's time by interviewing for jobs you don't want. With that said, if the first interview you do in years is for that One Perfect Job, you probably won't succeed because interviewing is a perishable skill.
You've got a job. It's a fine job. You're making good contributions and your work is appreciated. That's all well and good, but you won't score a job offer based on talking about your current work performance. You can't even score an interview based on that. Scoring an interview is a topic for another day though. Let's assume you've scored an interview.
In the worst case scenario, you're going to interview with a bunch of complete strangers. They've reviewed your resume [0], they know what you're capable of doing, and they believe your skills are a good fit – otherwise, they wouldn't interview you – but now they have to like you; like you enough to want to work with you on a daily basis. The “culture fit” as they call it. And they only have a few short hours to make that determination.
Presumably, you can walk into this interview and dazzle them with your technical knowledge, but they probably have half a dozen other candidates who can do the same thing. Why you? And I think that’s the element that is most perishable. In an hour long interview, how can you answer a bunch of overused and rehearsed technical questions while simultaneously showing the interviewer what an amazing coworker you would make.
Not to disappoint you at this point, but I can’t tell you how to do that. There probably exist some general tips and tricks about word choice, eye contact (if you’re in-person) and so on, but I think a lot of it comes from feel; from practice. Like structuring code in an elegant fashion, or solving an equation in a beautiful way. You know it when you see it, and if you want to do the same, you need to practice. You know when you hit it off, and you know when you’ve flubbed it.
In conclusion, practice interviewing. Don’t be alarmed if you don’t get 2nd / 3rd round callbacks on the first few opportunities. Spread your job search net wide. Get in some good training interviews in preparation for the real thing. Be ready when you’re finally interviewing for that perfect job.
[0] You would think. I once did a half-hour preliminary interview after being contacted by a recruiter. At the end, the interviewer asked how many years of Ruby experience I had. "None; I've ever typed a single line of Ruby." It turns out it was a full-time Ruby development job. He clearly didn't spend even thirty seconds reviewing my resume before wasting my time. In fairness, I should be more diligent in reading the job description and asking questions before agreeing to talk.