If, for one second, you think he does this on purpose, and is some sort of genius media manipulator, you have massively misjudged him.
He is an impulsive idiot with the thought process of a moronic, self centered teenager. There is zero evidence that he is a considered thinker, and a very large body of evidence, and professional opinion, to say that he is mentally ill and extremely immature and unstable.
You are a fool if you look up to this worm and believe he is some kind of clever 'man'. He is a child. A vindictive, cruel, heartless, racist, selfish, impulsive, embarrassment. He needs gently leading away by the elbow and placing on a beach or near a golf course somewhere, so he can eat and drink himself into a hedonistic stupor while thinking his nasty thoughts about women and ethnic minorities. Make America great again? You've had some very inspirational leaders. Giants among men who had a very crystal clear sense of right and wrong and whose words are quoted, like these high ideals from John Adams:
"“If national pride is ever justifiable or excusable it is when it springs, not from power or riches, grandeur or glory, but from conviction of national innocence, information, and benevolence.” John Adams, 1797-1801
The last word in that quote does not describe a quality that Trump has. He is a massive embarrassment to the USA, and a dark stain unworthy of his office.
It's hard to deny that he is controlling the narrative. It's also very likely he's doing it deliberately, but that doesn't mean he's a genius manipulator or even remotely smart...or that he's not suffering from dementia (It's clear he's drastically changed from the early 2000's)
A headline drops "Trump campaign official's guilty of being terrible people", he get's angry and wants to be reassured everything is fine and turns on Fox News. Fox News is showing discredited stories which are either positive for him, claim the Russia investigation is a witch hunt or say something negative about Hilary Clinton, but they don't make it to the mainstream channels because they're made up, so not real stories. When he Tweets about them, they become news that the other channels can cover. He's their source, even if the story is "President believe something ridiculous", it still gets people talking about something other than what it was that was upsetting him earlier. He's learned that going on Twitter and Tweeting a conspiracy theory changes the subject.
It doesn't take any level of intelligence and will harm him in the long run, but he's only able to think about what's happening here and now. He doesn't appear to have the capability to judge an action on a time scale longer than a few days.