A novel of any genre should be based on a unique plot. Impossible; there aren’t any unique plots! Agreed, but the author of a novel worth reading will have presented a familiar one so differently that it won’t be recognized.

Take as an example, Romeo and Juliet. Shakespeare described his title characters as “star crossed lovers”, and they are – two people whose families are deadly enemies fall in love. It is a theme that has been used often with success because the differences lie in the reason families, employers, or society, are against the relationship – how the couple met – whether the story is contemporary, historical, or has a dystopian setting – it might be fantasy, but even the inhabitants of imaginary planets need a reason why an alien isn’t an acceptable mate.

Characters must step off the page and stick in the readers' minds. Heroes and heroines should be people with whom readers can empathize instantly and nobody is perfect. Suppose you want a handsome hero, usually a good idea, who might have a secret fear of public speaking. Attractive heroines could struggle to cope without their reading glasses. Both those ideas could drive a plot if it was vital that he stood up and defended what he believed in, or she missed a ransom demand for her child! Believable villains may be evil, but not entirely bad without a reason. It could be rooted in their past, or for the truly evil, lust for power, riches, sex.

How people speak needs care. One character who says “Err...” or “No problem” is a plus. Scatter such phrases at random and it loses impact. The “it’s Bill” before you mention a name, or, “Shona isn’t taking this seriously again” moment, when the reader feels part of the story.

Whichever plot you choose to make your own, the setting must be right. Research is needed for a historical novel, but if you want to make “contemporary” strong, it is equally demanding. Trains must run on lines that exist and commercial aircraft use real airports. If you feature a helicopter, it frees you a lot, but remember it will need to refuel, and the place shouldn’t be imaginary, or specific. “They dropped down over the Northumbrian coast to refuel” is fine, provided there is a facility in that area.

The author of a novel worth reading never cheats. Every story in any genre has secrets, not just in detective tales and thrillers. When you reach the denouement and that secret is revealed, the reader should think “why didn’t I guess? It’s obvious!” – the secret of the secret is hiding it in plain sight.

Finally, wherever you live, never forget that North America is the biggest market. I am not suggesting that you set your story in the USA or attempt to use American English if you're not an American, but don’t leave readers puzzled either. For instance, upmarket magazines in the UK are known as “glossies”, but the safe alternative is to name one or two you’ve checked are sold worldwide.