One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(25,26,31,35,30,36,29,34)(27,32,38,46,40,48,39,47)(28,41,42,33,44,49,43,50)(37,51,53,45,54,56,52,55)(2,5)(6,8)(9,10)(11,15)(12,16)(13,14)(17,23)(18,21)(19,24)(20,22)(25,27)(26,32)(28,37)(29,39)(30,40)(31,38)(33,45)(34,47)(35,46)(36,48)(41,51)(42,53)(43,52)(44,54)(49,56)(50,55) involution — undirected(1,3,4,7)(2,6,5,8)(10,14)(15,21)(16,22)(23,24)(25,28)(26,33)(27,37)(29,42)(30,44)(31,43)(32,45)(34,49)(35,41)(36,50)(38,52)(39,53)(40,54)(46,51)(47,56)(48,55)(9,11,13,18)(10,15,14,21)(12,19,20,17)(16,24,22,23)(25,29,30,31)(26,34,36,35)(27,38,40,39)(28,42,44,43)(32,46,48,47)(33,49,50,41)(37,52,54,53)(45,51,55,56)(9,12,13,20)(10,16,14,22)(11,17,18,19)(15,23,21,24)(25,29,30,31)(26,35,36,34)(27,39,40,38)(28,42,44,43)(32,46,48,47)(33,41,50,49)(37,53,54,52)(45,51,55,56)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.