To attack [Trump] effectively, you have to go after the things that people like about him. You have to flip his brand.
So don’t tell people that he doesn’t know the difference between Kurds and the Quds Force. (They don’t either!) Tell people that he isn’t the incredible self-made genius that he plays on TV. Tell them about all the money he inherited from his daddy. Tell them about the bailouts that saved him from ruin. Tell them about all his cratered companies. Then find people who suffered from those fiascos — workers laid off following his bankruptcies, homeowners who bought through Trump Mortgage, people who ponied up for sham degrees from Trump University.
Or just take a camera crew around Atlantic City, and slap Trump’s name on what you find.
Likewise, don’t get mired in philosophical arguments about big government and crony capitalism. Find the people hurt by Trump’s attempts to exploit eminent domain: The widow whose boarding house he wanted to demolish to make room for a limo parking lot, the small businessmen whose livelihoods he wanted to redevelop out of existence.
(One of the Donald’s foredoomed rivals, Ted Cruz, actually just cut an ad along these lines. But of course it’s too late for that to work.)
Finally: Calling Trump out for having “New York values” when you mean “thrice-married, coarse, and libertine” is telling people what they already know. If you want to persuade his voters that his “New York values” are a problem for them, put his alleged dealings with the Mafia on the table.