Suspense is a feeling of pleasurable fascination and excitement mixed with apprehension, tension, and anxiety developed from a unpredictable, mysterious, and rousing source of entertainment. http://en.wikipedia.org/wiki/Suspense

Instructions

1) Place your character(s) in precarious positions that force them to make hard choices as a matter of survival. The danger can take the form of physical harm such as a chase, accident or disease, an ultimatum to choose between two desires, or even a crisis of faith that challenges previously held beliefs. Consider rock-and-a-hard-place scenarios that put ordinary characters into extraordinary positions that test their mettle. Television series frequently use cliffhangers for their season finales to keep audiences guessing for the next several months which characters in the cast will survive a tragedy, disrupt a wedding, announce a pregnancy or see something that they weren't supposed to. These same set-ups work for chapters in novels as well by escalating the stakes at every turn.

2) Create a context for your characters to have a conversation that will trigger an unexpected revelation. Example:

Your heroine is eagerly telling her fiance about the latest plans she has made for their upcoming wedding. He suddenly takes both of her hands in his and utters the four most dreaded words in relationship history: "We need to talk." Is he about to tell her that he's already married? That he just lost his job? That he has enlisted in the military? That he's dying? That he has been living a secret life? That he accidentally ran over her cat? Inquiring minds will want to know.

The only way the reader can find out what he tells her is to quickly move on to the next chapter. To put the reader in an even more heightened sense of suspense, consider starting that next chapter with a completely unrelated scene or jump ahead a few months and show the heroine with a different beau, living in a different city or attending a funeral.


3) Insert a twist that your audience didn't see coming. This works quite well with thriller and horror genres if you can lull viewers into a false sense of security that they know what's going on. By supplying them with enough red herrings that point to the villain being someone else, they will then be caught completely off-guard with a cliffhanger that points to the contrary. Example:

A town is celebrating that the killer who was terrorizing them is finally dead as a result of drowning in the river. Readers know from the previous chapters that he always wore a distinctive ring and that he had a creepy catch-phrase he liked to say to his prospective victims. While the villagers are busy carousing with gusto, a family in another town across the river is awakened by a knock on the door. Being kind and charitable people, they welcome the cold and soaked visitor into their humble abode and offer him food and lodging. We see the ring. We hear the creepy catch-phrase. If it's the last chapter of the book, we also see a sequel in the works.