One of the main points I took great notice of was to watch what is in the frame. Whilst watching previous student's horror film openings, there were several times when everything we could see in the frame was not necessary to the film. And so instead of seeing what we only needed to see; the two main characters, we saw a large couch and coffee table taking up most of the frame. This made me aware that it isn't really pleasant or helpful to show anything else apart from what is necessary to the film and I will now definitely be cautious of what I put in the frame.
Another observation I made was that in order to build tension, it is nearly essential to use tension building/mysterious non diegetic sound. Like this:
When I was watching the previous A Level work, the times when students tried to build suspense and scare us, didn't fully frighten me. I thought it was lacking something, that horror films normally do not slack on and I think that was tension building sounds. After watching some horror films, (in comparison to the A Level work) at all tense times, there was either non diegetic sound or significant Foley sounds used - and that's when I was able to note that scary tension/suspense sound is essential when trying to build tension and scare the audience.
Dialogue. I learnt that dialogue is not a necessity to be in the first two minutes of a horror film to make it interesting and attention-grabbing. Nor is screams, blood and knifes. From the previous A Level work we watched, the most successful ones were often those that had minimal to no dialogue but instead just sounds necessary to the film.
Likewise to the movie Sinister (which is the horror film that we took the most inspiration from whilst coming up with our opening concept) there is no dialogue during the opening: