You will not be boring. Or at least you’ll do your best not to be boring.
By the laws of the aesthete, "boring" is the most damning indictment possible for any work of art. The problem is, "boring" is a subjective term for which you will never get a consistent set of examples.
Here is a list of things people I know have called boring: Blade Runner, Citizen Kane, The Brothers Karamazov, Dos Passos's U.S.A. trilogy, Asimov's Foundation series, The Tale of Genji, Star Wars, 2001, all of Shakespeare, the first four Black Sabbath albums, Casablanca, Miles Davis's Kind of Blue, and all three Transformers films. The list goes on. A purely inclusive list of boring things, based solely on someone's insistence, would end up encompassing most every work of art or culture.
What makes something boring, then, has little to do with the thing itself, and stems almost entirely from peoples' expectations.
The way peoples' expectations are set up and played off is as much about marketing and promotion as it is about the work itself. If I go into 2001 knowing full well it's not a shoot-'em-up, I'm likely to have far more patience for it than if I expected laser blasts to be ricocheting across the screen. I suspect Rock Hudson's infamous walkout during the premiere ("Will someone tell me what the hell this is all about?") stemmed from just such frustrated expectations.
What's the best way not to be boring? One way to do this would seem to be: don't mislead the audience. Don't promise them something you never deliver, then blame them for getting your intentions wrong.
But how exactly is one to do that? One person's boring — even one person's unintentionally boring — is another person's fascination. If boredom is about the reader's expectations, then maybe it falls more to the reader to teach himself how not to be bored than it does to the writer to not bore him. Every writer thinks they're doing something intrinsically fascinating, and pooh-pooh to the audience who doesn't want to do the needed heavy lifting to follow along.
I do not feel I am caricaturing the expectations of many writers working today when I make such a statement. They regard the sophistication of the reader as a good thing, and I am inclined to agree: a smart reader is always preferable to a stupid one, and no author should feel they have to tailor their work to appeal to people who choke up on any word longer than four syllables, or which is about more than whatever is happening around them at that very moment.
But that doesn't stop them from writing things which many readers — even many intelligent, literate, patient readers — gag on. They are bored, not because their intelligence is not being engaged, but because their intelligence is being engaged at the expense of just about everything else that fiction is worth reading for. It's one thing to cater to an audience's brains, and another thing entirely to assume they want nothing but that, and in a form as rarefied and high-handed as possible.
The same thing happens in reverse, of course. We have plenty of authors who say things like "I'm just trying to tell a good story," and they mean it, and I believe them. And, for the most part, they spin a pretty good yarn, but if they get testy about fiction having higher ambitions I always feel like they're missing out on something.
Good fiction is not about tickling the higher brain functions alone, or the funnybone, or the heart. Each forms one component of it, but all need to be in sensible balance with the other reasons we pry open a pair of covers: to be entertained, to enjoy some sense of empathy or wonder, and to walk out of the book with something we didn't have when we walked in. A good book may have any one of those things done well, but a great one will juggle them all effortlessly.
How those elements are put into balance will vary. The way they were balanced for an audience of one hundred fifty years ago is different from the way it's done now, but not so different that there is nothing to be learned from the way it was done once upon a time.
The best way not to be boring, then, is to remember that being interesting is by itself a panopoly — that what draws people to a book, any book, is never any one thing by itself. You don't have to engage every reader, but engage the whole of any one reader if you can.