The goal is to make complex ideas understandable to people outside the area of expertise.
First, start out with a broad introduction. Then narrow your focus so that it gets closer and closer to your specific topic and point. Toward the end, start to broaden the paper again to focus on big picture.
Reference general psychology theories and come up with your own implications.
Arguments that are directed towards the general audience serve more “personal” purposes (e.g. raising awareness in families about parent-child interactions, persuading parents with children with mental disorders to act in certain way).