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