Fear and Society:
Horror films of today are shaped by a few basic cinematic principles but beyond that, when trying to make a great horror for the day and age you have to consider your society.
What are the fundamental concepts that scare people in your society?
This is how you decide who or what the antagonist should be. If you want to truly make a classic than history comes into play. You have to determine what scares people, what did scare people, and what will always scare people.
Atmosphere: You wouldn't chose a bright and sunny 50's cul-de-sac as the setting for your horror film. Setting really plays a huge role in how your film is perceived, especially when it comes to a film that is expected to be dark and suspenseful.
Suspense: Similar to setting, suspense is paramount in a horror film. You have to breed this feeling with sound and environment in order to drag your audience into a willing suspension of disbelief.
Jump Scare: Jump scares are really the cheap trick of the horror film industry. It is a sure fire way to get your audience on the edges of their seats and wanting to see more. The use of too many jump scares however will defeat the purpose and numb your audience to what it is you are trying to achieve.
