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