One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,8)(4,6)(5,7)(9,10)(11,14)(12,15)(13,16)(17,21)(18,22)(19,23)(20,24)(25,26)(27,36)(28,34)(29,35)(30,45)(31,33)(32,39)(37,53)(38,46)(40,52)(41,56)(42,50)(43,48)(44,51)(47,54)(49,55) involution — undirected(9,11)(10,14)(12,19)(13,17)(15,23)(16,21)(18,20)(22,24)(25,27,30,39,31,40,29,38)(26,32,35,36,33,46,45,52)(28,41,42,55,43,37,44,54)(34,49,51,56,48,47,50,53)(1,3,5,4)(2,6,7,8)(11,17)(14,21)(18,19)(22,23)(26,33)(32,46)(34,48)(35,45)(36,52)(47,49)(50,51)(53,56)(9,12,13,20)(10,15,16,24)(11,18,17,19)(14,22,21,23)(25,28,31,43)(26,34,33,48)(27,37,40,41)(29,44,30,42)(32,47,46,49)(35,51,45,50)(36,53,52,56)(38,55,39,54)(1,4,5,3)(2,6,7,8)(10,16)(14,21)(15,24)(22,23)(25,29,31,30)(26,35,33,45)(27,38,40,39)(28,42,43,44)(32,36,46,52)(34,50,48,51)(37,54,41,55)(47,56,49,53)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.