Finding the perfect pair of jeans can be like looking for the Holy Grail—a bitch, but when you finally hit pay dirt, you're set for life. Jeans are America's uniform, and a good pair can rock a room like nothing else. But darling, they need to be purrfect. I've bought a lot of good-enough jeans of late, from $340 Diesel skinny jeans that covered everything wonderfully except my crack, to $10 Levi's from Ross that—although comfy and cute—didn't quite do my ass justice (please note: "comfy" and "cute" should never be anyone's sartorial goal). So, with fall around the corner, I took Merc fashion maven Marjorie Skinner's advice and put myself in the capable hands of JoAnne Woods, who specializes in wrapping curves and crevices in top-end denim. A psychology student and self-described clothes addict, JoAnne's put some thought into why we spend a fortune on the most utilitarian part of our wardrobe. The verdict? "To attract a mate."

What are the challenges most people have when being fitted for jeans?

They see themselves as having big thighs or a big butt, but I think they just haven't come here. We know our jeans really well, and which jeans fit which body types. A pair of jeans that's not the right fit can make a great ass look so bad. I'll see women walk down the street and think, "No, no! Come to me! Let me help you!"

What sizes do you accommodate?

Size 24 to size 33 in women's, and up to size 38 in men's.

Why can't they make jeans that cover a gal's ass crack?

They're starting to. We have a new mid-rise section that's the perfect fit—just above a low-rise but much lower than the high-rise "mom jeans."

Trends for fall?

For women, this is the first time that I've seen every kind of style come through the door, from high-rise wide leg to low-rise skinny leg and everything in between. For men, as jeans are being accepted more in the work force, there's a big demand for a nice clean fit or a dark dressy denim.

Do you have any secrets for extending the life of your investment?

Wash jeans inside out on cold and don't stick them in the dryer. That'll preserve the color, the shape, and the weave. Also, try not to wash them very often. You'll hear designers say, "Never wash your jeans." I don't know who can do that, but if you have a handful of pairs, you can rotate through them. VIVA LAS VEGAS