I am not sure you can talk to evangelicals about evolution. But first, a qualification: not all evangelists are fundamentalists. Mainline (non-fundamentalist) evangelists can even be somewhat liberal, in terms of social issues at any rate. So perhaps it is possible to reach some of these people. As for fundamentalist evangelicals, I find the following anecdote useful:

*Guy gets on a plane and finds himself seated next to a cute blonde. 
He immediately turns to her and makes his move. "You know," he says,
"I've heard that flights will go quicker if you strike up a 
conversation with your fellow passenger. So let's talk."

The blonde, who had just opened her book, closes it slowly and asks
the guy, "What would you like to discuss?"

"Oh, I don't know," says the guy. "How about nuclear power?"
"OK," says the blonde. "That could be an interesting topic. But let
me ask you a question first.
 
A horse, a cow, and a deer all eat the same stuff-----grass.   Yet the deer excretes little pellets, the cow turns out a flat patty, and the horse produces muffins of dried poop. Why do you suppose that is?"

The guy is dumbfounded. Finally he replies, "I haven't the slightest idea."
"So tell me," says the blonde, "How is it that you feel qualified to
discuss nuclear power when you don't know shit?"

I believe that trying to reason with fundamentalist evangelicals about evolution and most other subjects is roughly equivalent to the blondes dilemma.

[Sadly, I don’t recall the source of the above. Otherwise, I would reference it.]

I grow tired of the same tired and ignorant arguments against evolution from creationists, specifically:

If we're descended from monkeys, why are there still monkeys?

Evolution is only a theory.

Evolution is a religion.

I believe he'd think what most of us think, that the evidence supports his theory and anybody who doesn't agree either doesn't understand or simply won't look at it.

“Darwin provided an explanation for life’s origins“

I don’t think he does. On The Origin Of Species. It’s right there in the title. It gives a natural explanation for the variety of life we see. It doesn’t say a thing about it’s origins.