In the book, he describes his disguise as consisting of coloured contact lenses, makeup and an afro wig. He said no one recognized his disguise during his reporting.
So not really what John Howard Griffin did:
In late 1959, John Howard Griffin went to a friend’s house in New Orleans, Louisiana. Once there, under the care of a dermatologist, Griffin underwent a regimen of large oral doses of the anti-vitiligo drug methoxsalen, and spent up to 15 hours daily under an ultraviolet lamp for about a week. He was given regular blood tests to ensure that he was not suffering liver damage. The darkening of his skin was not perfect, so he touched it up with stain. He shaved his head bald to hide his straight brown hair. Satisfied that he could pass as an African-American, Griffin began a six-week journey in the South. Don Rutledge traveled with him, documenting the experience with photos.[2]
During his trip, Griffin abided by the rule that he would not change his name or alter his identity; if asked who he was or what he was doing, he would tell the truth.[3] In the beginning, he decided to talk as little as possible[4] to ease his transition into the social milieu of southern U.S. blacks. He became accustomed everywhere to the “hate stare” received from whites.
Of course, Griffin also did it in a place where it was far more dangerous to be black, or even to sympathize with the black experience in the South. In fact, a few years after the book came out, Griffin got pulled over and beaten in Mississippi because of the book.
Griffin risked his life and his health to tell the story of how black people in the American South risked their life and health on a daily basis.