Trend Watch: Lea Michele, Jessica Alba + More Rock Sideswept, One-Shoulder Waves

Nothing is murder on hair like summer's heat and humidity. Whether you have straight, shiny locks or coarse 'n curly tendrils, warm air interferes with sleek, polished styling.

A possible fix? Sideswept, one-shoulder waves.

It's an intentionally messy style -- in fact, the messier, the better. You can get away with not washing your hair, using little product and avoid further sweating from the blowdryer and flat iron.

Lea Michele:

The 'Glee' star's ombre highlights and deep side part are effortlessly bedhead-y. It's the epitome of wash and go.

Jessica Alba:

The actress and mom of two toddler daughters doesn't have too much primp time, and she looked amazing with thick, single shoulder waves. It may not look it, but this style certainly required some added effort with tools and product. Even so, it's gorge.

Zoe Saldana:

The 'Star Trek' beauty kept her hair out of her face at Cannes with the aid of braided headband, which appears comprised of her own strands and left her locks to fall on her shoulder with grace and poise.

Kerry Washington:

Thick waves with a peek-a-boo red stripe were a win-win for the raven-haired bombshell. Notice how having waves on one side of her head plays up her eyes, cheekbones and bone structure? Her hair -- which is a bit curlier, thanks to an iron -- calls attention to her lovely face.

Nina Agdal:

The Sports Illustrated model and rumored Adam Levine paramour has a thick mane, so a loosely falling cascade still frames her face. But it looks like she just tosses and goes.