Donald Trump said on "The O'Reilly Factor" tonight that he's just going to be himself at Thursday's Fox News-Facebook Republican presidential debate.

Trump said that he's confident in his message: The country is going downhill fast, we have to stop it and he's the one to do it.

O'Reilly pointed out that the moderators of the debate, Megyn Kelly, Bret Baier and Chris Wallace, will be asking specific, substantive questions.

"I want to talk about policy, I want to talk about the wall [on the U.S.-Mexico border], I want to talk about illegal immigration, I want to talk about bad trade deals," Trump said.

O'Reilly emphasized that Kelly, Baier and Wallace will press him for specifics on, for example, how he would get Mexico to build a wall along the southern border.

Trump said he's "totally ready" to do that, arguing that Mexico is making billions and billions of dollars by "killing" the Obama administration on trade deals. 

"I'm gonna say, 'Mexico, guess what: This is not going to continue. You're gonna pay for the wall.' ... They will pay for it," said Trump.

He added he's not planning on going after his fellow GOP contenders, but he won't be afraid to fire back if anyone takes a shot at him.

"I have certain abilities that they do not have," Trump said. "I'm not looking to hurt anybody, I'm not looking to embarrass anybody. If I have to bring up deficiencies, I'll bring up deficiencies. But certainly I'm not looking to do that."

"People are tired of incompetence. They don’t want incompetent people running our country."

Watch the must-see "Factor" interview  above.

Don't miss the Fox News-Facebook Republican presidential debate, Thursday August 6, live from Cleveland, Ohio at 8:50p ET, moderated by Megyn Kelly, Bret Baier and Chris Wallace. 

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