C'mon Bible Belt. You can do better than that. Glib isn't cool.
It's several ways. But I will tell you this, the more you push and make it an issue, the more you "talk" about it...the more you won't get it. Like all things with a woman you lead her to it. It's been some years since I've talked a girl into giving head but it was never from the position of I ate you out, so you owe me. Nobody likes to feel obligated.
This is what I used to do. We are having foreplay, kissing and touching each other. I kiss her all over,play with her a bit and get her going. I may nibble on her fingers and suck on them during foreplay. At some point I'll rub my fingers across her lips and maybe tell her to suck on the tips of my fingers. Then at some point I'll lay on my back and let her kiss me. Then I'll tell her to kiss my chest and rub my cawk at the same time. Then I'll tell her to kiss my stomach. Then I'll tell her to kiss the tip. If she balks, I'll say...just kiss it like your kissing my cheek. If she does that, good, if she gets upset, I usually back off and go back to foreplay. Next I'll tell assure her that it only tastes like skin, just stick your tongue out and see, nothing is going to happen. If she does that, I'll tell her to lick it around the head, not asking her to put it in her mouth yet. I'll try to give her some positive reinforcement by telling her how great that feels. Then I'll tell her to lick it up and down, after she complies with that I'll tell her to put the tip in her mouth, of course always telling her how great she looks and how great it feels. And then I'll talk her into taking more until she's finally getting it right. Of course if she's never done it you have to remind her not to use her teeth and assure her you will let her know if your about to ***.
It's all about leading her to it slowly, making her comfortable at every step and letting her know she can trust you.
Some girls have issues and they just aren't going to do it, but some can be talked into it. It's up to you to be charming, strong, and lead her to it and make her feel good about it.