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