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