Pop psychology is often like this blog post: Lazy. This blog post and pop psychology, however, use different techniques. This is just me spouting something off the top of my head without any research. Pop psychology will often grab one study and then overgeneralize, telling you how this changes everything. It will make you feel clever by telling you how this study is counterintuitive and subverts the status quo. Then, it tells you how you can apply this to your own life. Although there are no studies to back up this application, the author has a lot of anecdotes, culled from months of confirmation bias.
I must remember to get closer to the source. One simple heuristic: Distrust psychology books written by journalists.