Famous hairstylist John Frieda says that most people fall into one of two groups: those who are lacking volume and those who are looking to tame their frizz. I've got you covered on the latter, and as for the former, here's a quick tip from the legendary stylist on reviving limp locks.
If you have no time to wash and style your hair, you can pump up the look with three basic ingredients: a round brush, a blow dryer, and a volumizing product, like Luxurious Volume Lavish Lift Root Booster ($6) or Oscar Blandi Volumizing Spray ($18). First, hold the hair straight up on dry hair and spray the roots. Next, take a small section from right behind the fringe, wrap it around the round brush, and blow-dry, concentrating on lifting the roots for volume. Finish off by grabbing subsequent sections of hair back toward the crown, and there you go. It's instant volume without too much effort.