Your heart is slamming
against your rib cage, your
fingertips are moist and you
turn another page. The
antagonist is setting up a
trap. You wish you could do
something to prevent the
protagonist from walking
into it, but you can’t. You’re
helpless, totally at the
mercy of the writer. All you
can do is turn another page.
If you’ve ever felt this way
reading a book, then the
writer has done a great job
of creating suspense. If you
continue to feel this way
until the last page, the
writer has also done a great
job maintaining it. That’s no
easy feat, as you’ll discover
when trying to write a
suspense thriller.

1. Dramatic Irony

Let the reader see the points of view
of both the protagonist and
antagonist. This narrative mode is known
as the third person omniscient. It will
allow the reader to see when the
protagonist is making a mistake and about
to run into trouble. Let the reader see the man who is in the bush waiting in ambush for the protagonist who thinks he is alone. The reader will be helpless to
prevent the disaster that's coming and so wants to know what happens next. Does the protagonist escape? Does he get killed? Does he get kidnapped?

2.Create a really good protagonist/hero.

Katniss Everdeen from the Hunger Games novels by Suzanne Collins happens to be one of my favorite. She becomes the really good hero in just nine pages. How? She volunteered herself to save her sister. Let your protagonist do something unselfish but difficult. Let your hero be the hero and don't let it happen easily. Create a truly heroic protagonist that
the reader will identify with. Give him or her allies, enemies, quirks and skills. The
reader will worry about what might happen
to her. Maintaining suspense is easier
when the reader cares about the
protagonist.

3.Use time limits.
Another key way to build
suspense is through the use
of time. The protagonist
should be working against
the clock, and the clock
should be working for the
bad guys. In Rogue Nation, the protagonist Ethan Hunt has to get some files from an underwater reservoir but he can only hold his breath for a shorter time. This makes him work and think faster. Let the protagonist work under limited time. Now that's a tool for suspense.

4. Keep the stakes high for the protagonist.
This doesn’t necessarily
mean the story’s hook has
to be about global
annihilation. But the story
must be about a crisis
that’s devastating to the
protagonist’s world, and the
hero must be willing to do
anything to prevent it from
occurring. Therefore, the
story could be about a
father trying to rescue his
wife and child from an
impending flood, or an
innocent man who’s framed
for murder going on the run
to establish his innocence.
The crisis has to be
important to ensure readers
will empathize with the
protagonist. Whatever it is that the protagonist is
trying to accomplish in the story, failure
means utter devastation to everything the
protagonist cares about.

5.Complicate matters.
Pile on the problems. Give the
protagonist more things to
do than he can handle. The
hero has to be stretched
wafer-thin. If you’ve ever
seen one of those old
music-hall acts where
spinning plates are perched
on top of flimsy bamboo
poles, and there’s some
poor guy running himself
ragged trying to keep all the
plates from crashing down,
well, that’s how it should be
for the protagonist. The
hero should be that guy
trying to keep all those
plates spinning, while the
antagonist is forever adding
another plate to the line. By
the end of the book, the
protagonist should be just
barely preventing everything
from crashing to the
ground.
Let’s use The Altman Code
and 24 Hours as examples. In The Altman Code,
Jon Smith’s problems are
further complicated by
having to break the
president’s father out of a
Chinese prison camp. In 24
Hours, Will and Karen
Jennings’ daughter is
diabetic, and the kidnappers
don’t have her insulin. Both
these examples add another
layer of complication to
their respective stories

You can read all about it on my book titled 12 secrets to creating suspense. Free download links will be made available soon.