Economic success is usually built on confidence (assuming that economic policy is sound).
If he talks up the American economy and America buys into it, it will lead to a pick-up in the economy.
If he persuades the multinationals to stop outsourcing jobs to cheaper countries and produce more at home, then this will help. Globalisation hasn't really help the average person much - it suits the elite/large corporations IMO.
If he stops the insane policies of climate change then this will be a benefit to the economy. (No, I'm not a denier, but I am sceptical about climate change and yes, I have done a LOT of reading on the subject).
Regarding climate change, I agree (and I'm a so called scientist). Yes, there has been an increase in this and that in parallel with consumption of fossil fuels but . . . . the swings in the past are massive in comparison. To me its likelooking at the increasing cold in November and January and predicting a new Ice Age by August.