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