Keep in mind that not all characters will react to anxiety and crises in the same way. Spend some time figuring out how characters react to suspense, anxiety, and fear. Try to avoid the usual descriptions, such as "her pulse raced..." If you're at a loss for descriptions, remember the last time something scary happened to you. What happened the last time you stepped on the breaks and your car tried to skid? Did your stomach feel like a brick? Did you shriek, or swear? Or did you steer yourself out of the skid and only respond to the stress after you were safe? Use those experiences to color your characters' reactions.
Omit excessive detail. Some of the best scary stories skillfully leave it to the reader's imagination to fill in the blanks. It is often what is hidden, or merely hinted at, that sends chills down the spine.
Craft a tense and suspenseful tone. Focus on more than just the scary abandoned buildings or creepy old mansions. Characters reflect tone by how they react to events as they unfold: if the characters are convincingly tense and uncertain of what's around the next corner, chances are your readers will be as well. Throw some twists and turns into your story, surprises that your readers will not see coming.
Hitchcock believed suspense didn’t have much to do with fear, but was more the anticipation of something about to happen.
What is scary is very subjective, so it's best to write something that scares you.
Try writing about an actual event that scared you in your life. My first horror story I ever felt comfortable sharing (long since lost, of course), involved a string of events that I'm still convinced were caused by a ghost in my house. The genuine nature of the story to me allowed me to effectively tell it to other people. Since I thought it was real, I wrote it like it was real, and that is what scared people.
Writing Horror Literature (Justin Daniel Davis)
What scares people? And how do I tap into it?Well, a good place to start as a source of fear would be the most logical and often overlooked one: yourself. Face it...you’re rarely going to get anywhere by trying to capitalize on what you THINK scares people. Start with yourself...not only is this your most reliable source, but your writing will come across as more genuine, less artificial. What scares you? Monsters under your bed? Loss of control? Ghosts? Goblins? Chores?
So...what scares you? Do you have any tips to share to add a touch of creepiness to stories, maybe just enough to have your reader on the edge of her seat?