The hottest (and easiest) hair trend right now is BRAIDS!!!
It started last year with the "headband braid" perfect for keeping long bangs out of your face (nearly made popular overnight by Lauren Conrad when she wore the look on the Hills)
and NOW, Spring 2011 its all about the "side braid!"
I love the messy on top look, rather than the tight 'pulled back' braid.
To start, use a texturizing cream and air dry your hair (perfect for a hot day) using a smoothing cream on the top of your strands, smooth hair (lightly, don't pull) to the side and start braiding. As you can see from the photos, the look is more natural and messy - so if pieces stick out, just go with it. Secure with an elastic. Better yet if you treat yourself to some decorative elastics or rhinestone clips to secure the bottom.
Spray with hair spray, and bobby pin back any parts you don't want hanging loose.
Also becoming popular this year, is the "Fish Tail" or "Herringbone" braid:
It takes a bit of practice, but you can print these directions and practice!