The role of an interior designer is to create design harmony within a home or a single room by using a color scheme to match textiles, furniture and accents. A professional interior designer must also be aware of fire codes and laws. Designers can practice without a license, often within a large agency. To become a certified licensed practitioner they first must gain experience. The credentials required for certification vary by state, but most states have similar requirement categories.
Educate yourself. To practice interior design with any firm, even in an entry level position, post-secondary education is required. Design and trade schools offer training that can be completed in two to four years. A four-year graduate receives a bachelor's degree in design, while two- and three- year graduates receive an associate's degree or certificate.
Enter an apprenticeship program offered through your school or through the National Council for Interior Design Qualification, which helps entry-level interior designers gain experience. Many states require interior designers to have a certain amount of work experience added to their years of education to get a state license. In California, interior designers must have six to eight years of combined education and experience to get a license. An apprenticeship not only lets you to work toward your experience requirements, you can also knowledge and contacts during the process. Georgia and Puerto Rico designers do not need to gain experience before taking the board exam.
Take the National Council for Interior Design Qualification test. This test is given over two days every six months in many states and parts of Canada. The test is made up of three parts: codes, building systems and construction standards; design application, project coordination and professional practice; and interior design practicum, which takes an entire day. The purpose of the exam is to test the applicant on facts relevant to the safety and welfare of the public. Applicants must pass all three sections to gain a license. As of 2011, the registration fee is $165, with a supplemental fee of $55 for missing information.
Remain active in your education. To maintain a valid license an interior designer must continue to take courses. Some states require designers to take as little as a half-credit course each year, while others require 10 credit hours every two years. In Colorado, Connecticut, Virginia, Illinois, Maine, Indiana, Nevada, Michigan, Oklahoma, and New York, interior designers do not need to take continuing education courses to renew their licenses.