As you write your novel, screenplay, article or short story look for ways to build in some surprises for your reader. It's a pleasant feeling to realize that what we thought was going to happen isn't what actually does (at least it's pleasant in books and films; in real life we may not appreciate it as much).
The surprise may be the way a man we'd assumed is a coward suddenly steps forward and shows some courage, or an unexpected turn of phrase, or a twist at the end of a story.
Of course the challenge isn't thinking of the surprise, but making it plausible despite not being predictable. That means that the moment when the coward shows courage has to be out of the ordinary. It may be that he's afraid of his own shadow but the one thing he cares about is his dog and when that's endangered he'll do whatever it takes to save it.
Or we find out that the car mechanic who suddenly spouts something from Shakespeare is attending night classes in literature because he's always felt held back by his limited education.
And whatever that twist ending is, it has to make sense when we look back over everything that went before.
The more crowded the marketplace, the more important it is to surprise people. For instance, printed magazines are facing a tremendous challenge from their electronic competitors. Some publications have responded with features that surprise and delight. Examples include Mono.Kultur, which features a different binding every issue, La Mas Bella, the formats of which have included a map, an apron, and a tapas-making kit, and MK Bruce/Lee, which comes in two versions (Lee for women, Bruce for men) and includes fold-out posters, stickers, and other goodies.
Whether it's the writing itself, or your query letters to agents, publishers or producers, or your blog--look for ways to surprise your readers and they'll come back for more.
(My book, "Do Something Different," contains 100 case studies of inexpensive and innovative ways people have marketed themselves and their products. You can apply the same principles. The book is published by Virgin Books and features an introduction by Richard Branson. You can get it from Amazon or your other favorite bookseller.)