Showing a killers personality

I need to show more of my killers personality in my short trailer. The killer in my film is absolutely psycho and I am going to represent this by having her have a bunch of newspaper clippings about people she has murdered, in a folder called 'My achievements'. She will keep this in her car locked up in the glove box. In her car she will also have a bag of tokens that she takes from her victims, and she will place a necklace in this bag. I think this will represent that she is absolutely psycho.