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