You would usually be employed on the strength of your skills rather than your qualifications.
However, most professional graphic designers have a BTEC HND, foundation degree or degree in graphic design or another art or design based subject.
You will need a working knowledge of computer design software such as: Quark Xpress; FreeHand; Illustrator; Photoshop; 3D Studio; Flash. Courses in these are available at colleges and with private course providers.
Talent and contacts are the key to getting work, and you will need to keep an up-to-date portfolio of your work to show to potential employers.
Unpaid work experience will give you the chance to develop your portfolio, make contacts and impress employers. You could also create a website to showcase your work.
Competition for jobs is strong and not all jobs are advertised, so it is a good idea to network and make contacts within the industry, and to approach companies and agencies directly.