All states requires a cosmetologist to hold a license, but in order to qualify for a license you must graduate from a state approved school. Classes and training are often provided through state approved programs at vocational schools.
The length of training is usually around 9 months. Some cosmetologists go on to get an associates degree. Classes in sales and marketing are helpful for those that want to own their own salon.
On the job training helps to continue the education of new cosmetologists. Most salons will have new staff work on simple tasks, like shampoos and simple cuts before they are given their own chair and the freedom to handle all duties. On going professional training may also be required for a cosmetologist to stay on top of trends in the industry.
The state licensing exam is required and consists of a written test and in some states a practical test of skills. In some states training is credited towards the licensing requirement.