The civil services examination consists of three stages: a preliminary objective test (400 marks), a mains written exam with compulsory and optional subjects (1750 marks), and a personality test (275 marks). Candidates must have a graduate degree and be between 21 to 30 years old, with specific age and attempt relaxations for SC/ST and OBC candidates. The preliminary exam is qualifying, while merit is determined based on mains and personality test scores.