Dry your hair so that it is about three-fourths dry. You don't want to use a brush on extremely damp or wet hair because it can damage the hair.
Apply an egg-size dollop of mousse or a dime-size amount of styling gel to your hair. Mousse is better for adding volume and body; styling gel is better suited to reducing frizz and adding sleekness.
Choose a brush that is suited for the look that you want to achieve. Bigger round brushes are better for long hair, and smaller ones are geared toward shorter hair. Round brushes also help to create lift and volume. Paddle brushes and other flat brushes are geared toward smoothing and straightening hair. Brushes with vents in the body allow for quicker drying. Loosely packed bristles are suitable for adding volume; tightly packed bristles are effective in straightening.
Catch a section of hair with your brush that will fit comfortably onto the brush without falling off. Start with the brush near the the roots of the section, and lift the hair upward while blow drying the roots to add volume and body. If you want to straighten the hair, keep the brush level as you slide it through the section of hair while blow drying. If you want to add curl, roll the section of hair around the brush as you gently pull the brush through your hair. Rolling the hair over the top of the brush will create a curl that flips under, and rolling the hair along the underside of the brush will create a curl that flips upward.
Set your look with finishing spray if you want extra hold.