Before hunting for the handbook, one must understand the term. The "Young Fogey" (originally a pejorative coined in the 1980s by The Spectator and Private Eye ) refers to a young person who deliberately adopts the tastes, manners, and dress codes of a much older generation—typically upper-middle-class Englishmen from the interwar or post-WWII era.
The term "Young Fogey" was coined by Alan Watkins but popularized by the handbook itself. It describes a person—usually in their twenties or thirties—who adopts the dress, habits, and opinions of a much older generation.
: You may be able to view limited previews or finding information on Google Books [5.10].