Answer:
Classroom education? Very little. But to be a good guitar maker, you must have a lot of experience building them. The best way to go about doing that is to apply for an apprenticeship with a company that makes them. You will be able to observe professional guitar makers (known as luthiers), and have access to guitar making tools so you can practice making them. Most guitar makers are apprentices for about two years, but if you catch on quickly, you may be able to get hired sooner.