1) Go to bathroom and then get extra blankets so as to be completely comfortable. If you are certain you can handle it, make popcorn.
2) Arrange yourself on couch, bed, or other movie-watching surface. Place friends (or if you lack friends, pillows or stuffed animals) on either side of you and pile blankets on top.
3) Wrap one blanket about your head so your neck is completely covered. Leave only your eyes and mouth uncovered.
4) Draw legs up to chest.
5) Press play.
6) Keep one hand free, ready to pull blanket down over your eyes if needed.
7) Enjoy movie.
Just so you know, yes. This IS how I watch scary movies. I never used to be able to watch scary movies at all until I perfected my system.
Unfortunately, when I first saw Jurassic Park, it was in the theater, and I didn't have my system yet anyway, so I spent the entire movie turned completely around in my seat, trying to convince my brother that he had to go to the bathroom and I REALLY REALLY wouldn't mind taking him. (Remember, I was like 11 or 12, and he was 5 years younger. It was his birthday, which was the only reason I was in the damn theater in the first place. And yes, I'm still a wuss. But come on! Those velociraptors were DAMN FREAKY.)
Now I want popcorn.