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