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