For the quick and simple messy bun up-do, you will need about 5 minutes, your fingers, and a rubber-band. If you have more time, gather a soft brush, wide-tooth comb and an elastic ponytail holder. Preferably an elastic holder without a metal clasp to reduce the chance of hair damage.
For the most natural look, choose a hair spray with a micro-fine mist for minimal build up that you can apply and reapply without washing your hair. For a more extreme edgy look, choose a hair spray that offers massive volume without stiffness. If you have extremely soft or freshly washed hair, you can also experiment with dry shampoo or hair salt spray to add texture. (optional)
Pull the loop of hair further through the elastic ponytail holder to make the bun bigger and/or allow some of the strands to fall through for the ultimate messy look. Grasp the sides of the bun and widen the bun’s radius by gently pulling the edges out to the sides. Selectively tug on the center of the loop to give it more of a U shape. Pull the ends sticking through the underside of the elastic to the left and right so that they’re more flared out against your head. Tuck any unwanted fallen strands back into the elastic. If desired, wrap a few loose strands around the elastic and pin them with a bobby pin.
Apply two pumps of mousse to your hair starting at your roots and working the product to your ends. Back brush/comb your hair to tease it and create more volume. Brush the front of your hair down over your forehead. Then back-brush it by placing the brush in the middle of the hair and gently brushing back toward the roots; do this until the desired level of teasing is achieved. Repeat with the sides of your hair by lifting your hair and back-brushing again.