Donald Trump has no experience in politics outside possibly occasionally bribing officials and the attempted purchase of influence.
He does not understand the constitution - he doesn't know basics like the number of articles and doesn't seem to know much about any of the amendments other than referencing the second is a good way to draw applause.
He doesn't understand the limitations of executive power.
He doesn't understand even the basic workings of our military.
He does not exercise the judgement to surround himself with people who are good public servants - but instead has the soon to be indicted Chris Christie and the head of alt-right tabloid Breitbart as his inner circle. He has alienated huge swaths of his own party.
His education consists of barely getting through an undergraduate program at Warton Business School. He did not graduate with honors despite making that claim, meaning he was not in the top quarter of his class.
On the other hand you have Hillary Clinton, who has law degree from Yale Law with honors, was a member of Yale law review, was president of her graduating class at Wellesley. Served in public defense, served in on Children's Defense Fund, was one of the top 100 lawyers in America, was influential in education reform in Arkansas, served as a US Senator, served as Secretary of State. Is regarded by members of both parties as one of the most policy literate politicians in Washington.
It is okay to not like Clinton and her policies, but at the end of the day the job of President requires very much the same level of expertise as someone like a doctor. Donald Trump is a very good used car salesman, but he is not a doctor and he likewise has no competency in U.S. law. It behooves us all not to sign a contract for him to perform a rectal exam on us this coming Tuesday - I realize he has small hands, but he still doesn't know what he's doing, and like at least twelve women I haven't given him permission to grab my ass.