Pictured below are an illustration from Barrie’s novelization of Peter Pan and a still from the first film production (made while Barrie was still alive). Both display Hook’s iconic hook-for-hand, as well as his long, luxurious, black curls and 18th-century-looking frock coat.
F.D. Bedford, “Captain Hook and Peter Pan,” 1912, commons.wikimedia.org/wiki/File:Captain_Hook.PNG

“Ernest Torrence as Captain Hook in the film Peter Pan,” 1924, commons.wikimedia.org/wiki/File:Ernest_Torrence_as_Captain_Hook_in_the_film_Peter_Pan_(1924).jpg