Where’s the sweet spot between having a signature look and being stuck in a rut when it comes to your hair? Here’s how three beautiful women in the public eye pull it off.

Older pictures of Michelle Obama typically show her sporting a somewhat midwestern bubble. What a change to see her Jackie Kennedy-esque appearance at the Obamas’ first state dinner, for the prime minister of India! Normally Michelle looks best with a simple, mid-length bob and some bangs. Since she is tall, too much height on her head can be overwhelming. But that evening, her elegant updo was just breathtaking. This kind of versatility will serve her well as first lady, a position that wears many hats … or hairdos.

Once they find a look that works, many women seldom stray from it. In almost every shot of “Gossip Girl,” on a red carpet or at a Hollywood shindig, Blake Lively wears her hair parted off center and tousled. Only in one or two pictures does she have her hair up, and with her long neck, she should do this more often. While Lively always looks fantastic, a change now and then would be enlivening.

One of the great beauties of our time, Penelope Cruz, has two very different red carpet looks that keep us intrigued. She usually wears bangs grazing seductively above her eyes, her hair loose and sexy. Other times, her hair is pulled back and up, emphasizing her facial bone structure. She has also done a combination of both bangs and pulled-back hair -- her take on the iconic Audrey Hepburn Breakfast at Tiffany’s look.

Collaborate with your hairdresser to determine a couple of looks that will turn heads at every occasion.