Consider tension to be the thread that runs through the plot, subplots, and character development. Tension is created by a gradual build-up of suspense that becomes more intense as your protagonist's position evolves. Here are a few good strategies to boost the levels of tension in your writing, as recommended by promotional marketing services:

The event that started it all:
In most stories, the primary characters are involved in an inciting occurrence that sets everything in motion. It might be as simple as a critical choice or as spectacular as a fistfight, but it always changes the game and raises the stakes.

The clock is ticking:
In most thrillers, the clock plays an important role. Adding a time constraint to a story adds a little tension and adrenaline to it. For storytellers, a race against the clock—whether it's a literal clock or an impending deadline—creates natural suspense.

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To extend the scene and generate tension, use description. Make a hurdle for your characters to overcome, something to keep them occupied. Find strategies to make the description last as long as possible so that your viewers see it.

An unexpected story twist:
An unexpected storyline that no one sees coming adds drama by upsetting a character's well-prepared intentions. This can be hinted at via foreshadowing throughout the story. Your characters will have to adjust to their new conditions depending on the twist.