Read books that avert the masses. Read the same thing as them, and you'll think the same way. Think the same way as them and you'll act the same way, too.
Books that avert the masses induce a slight, healthy resistance.
This resistance to information-dense content, in reality, isn't aversion, but a sense of challenge—a challenge to develop your mental faculties.
As a bonus, the difficulty in understanding hard texts helps you retain them better.
Hard to understand texts—usually the older ones—make understanding the world easier. The high information density forces you to reread what you didn't understand at first glance.
Easier texts, on the other hand, are quickly forgotten; they encourage skimming more than digesting. Clickbait media atrophies your mental muscles—they're like alcohol for the brain. They feel good at the moment, but you'll forget everything the next day. (Arguably, the next minute.)
Reading intently, aside from meditation, is one of the few activities that actually make you smarter; it induces hypertrophy to your mental muscles.
Thus, the secret to a higher level of intelligence isn't genetics, but conquering increasingly difficult mental hurdles.