Have any presidential candidate from 1988 on prior speak fluent Spanish on television, preferably from humble Latin origins and with a solid educational resume. Maybe a Cuban family out of Miami or expats from Chile, Peronist Argentina, or Brazil would work too.
Honestly, I don't think it matters. The Republican Party thinks that by modifying its stance on certain policies they will bring over Hispanics. They never will. Getting a Latino face won't help much either. The GOP is pathetic, I honestly wouldn't be surprised if the party never regains the White House and is eventually absorbed into a more vigorous political organization. These guys honestly thought Mitt Romney was a good candidate and believed he had a chance. The encyclopedia has a picture of the guy under the entry for "stale toast".
The majority of Hispanics in the United States are Mexican, and they generally seem to agree with the Democrats' philosophy of government paternalism and heavy state economic involvement. I would attribute that to the poor socioeconomic circumstances of many Mexican immigrants, as well as the Catholic culture in which they were raised.
The only way that Hispanics would join the GOP in great numbers is if they viewed themselves as more upwardly mobile. That means that the makeup of Hispanic immigrants to the United States would have to change, or early immigrants have to do far better. Either Mexico will have to be a more stable prosperous country, or the immigrants will have to come from some other country. Maybe the majority of immigrants, instead of being the unwanted poor could be composed of middle class people seeking opportunity in an economically integrated North America.
Hispanics will gravitate more toward the GOP as their socioeconomic status improves and they become more assimilated. I personally don't think the GOP will be around to reap any award, though.