Here's another good piece that talks about the media and investments in a slightly different way. It talks about the "cover curse" and the housing market in 2018. Essentially, when you have several publications with bullish images or coverage of a market on their cover, it could be a sign of a top. Of course this isn't an exact science, but it could be a clue nonetheless. I'd take it a step further and watch for how many of your friends, family, or the media talks about a market that just keeps going, or you have to buy this stock or that stock. These can be ways to grab something that has momentum, but I'd caution to risk too much money on any of these types of "ideas".
You should purchase investments based on your goals and risk tolerance. If you go a step further, I'd even suggest purchasing investments from a business perspective. For instance, when you look at a company or even a sector, what do you think the long-term prospects are? Is it popular now or unloved? Does valuation seem crazy, reasonable, or cheap? These and many other factors are ways to look at and choose investments. There is no secret formula, and I'd even argue there is an art to it. All of this taken together can also help you screen for investments that may be at a peak or simply too expensive to purchase with reasonable expectations.
I'm happy to help you figure out where your investments stand in your bigger picture. Give me a call to get started.