Vanessa Williams Helms Beauty Ball

Vanessa Williams steps out in Vera Wang for March Of Dimes 33rd Annual Beauty Ball held at Cipriani 42nd Street in NYC.

How did the mother of four, 45, choose her outfit?

“Loved the color, loved the shape, loved the back,” she says. “A lot of the stuff this season is unconstructed, so this had a little bit of support, which is important. It’s really comfortable, so I don’t have to wear my Spanx and I’m loving it.”

Wait… she wears the shapewear?

“Of course! Doesn’t everyone? Especially when you’re wearing skin-tight stuff. I wear them on the Ugly Betty set all the time just to keep things pulled up and tight.”

Vanessa says her best beauty tip is finding the right shade of foundation for your skin type.

“No matter how well you do your makeup, if you see a big line and you see where it ends and begins, what’s the point?

Her choice? Laura Mercier foundation.

“My undertone is yellow. For me, I know what numbers I use and stuff, but it’s consistent enough that it gives you coverage and light enough that you don’t feel like you’re wearing a mask. The colors are beautiful. She does a great job. She did my face a couple times, but her line is fantastic.”

Vera is pleased that Vanessa chose her frock.

“She’s such a role model to all women with her courage, intelligence, her access and how strong she is in what she’s weathered in her life. She’s a real role model.”

Check out the OK! on stands now for Vanessa's outrageous-but-true beauty tip. "Jen's Magic Diet ...That Works!" is the cover line.