As you are looking to step up your career as an art director stop and take a look at the past few years of your career. If you feel it is time to take the next step and share what you have learned over the years, than as an art director you will be able to teach others. With that in mind, you will want to get your certification as an art director which can be done as through any art institute and most community colleges.  If you are at the beginning of your art career you want to pursue a four year degree in arts and design, from there apply for an entry level arts position, as an assistant teacher in a preschool or local museum. Offer classes in museums or volunteer your time to help build a portfolio and references.