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