3. Concentration on details
Another good trick for whipping up the atmosphere can be getting the right attention to detail. Why am I specifying which is "correct"? As details are a very powerful tool for the director, which can change the whole mood of a picture. For example, if the director concentrates the entire horror film on a beautiful woman's hand with a large ring, and at the end we see this large ring somewhere in the bushes, then we already feel fear. This detail has become a landmark for us, because we have seen it often and we already understand that something bad has happened. On the other hand, if we focus on insignificant details, it can turn our horror into a cheap drama, where the viewer's attention will be completely scattered.
This method is used all over the place, because these details give us, as viewers, the opportunity to understand that this thing needs to be paid attention to. For example, as in Peter Strickland's Little Red Dress, a charming black comedy with elements of a horror movie, the red dress serves as a huge bright accent from the very first minutes of the film, and then smoothly acts as the main antagonist. The play of colour, namely the combination of dark tones and bright details, acts as a psychological trigger that creates the suspense we need.