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)(25,26,31,44,30,36,29,35)(27,32,45,55,39,49,38,48)(28,40,41,33,43,34,42,50)(37,51,52,46,54,47,53,56)(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)(26,32,36,49)(28,37,43,54)(29,38,31,45)(33,46,50,56)(34,47,40,51)(35,48,44,55)(41,52,42,53)(1,3,4,7)(2,5,6,8)(25,28)(26,33)(27,37)(29,41)(30,43)(31,42)(32,46)(34,35)(36,50)(38,52)(39,54)(40,44)(45,53)(47,48)(49,56)(51,55)(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)(29,42)(30,43)(31,41)(32,47)(33,35)(36,40)(38,53)(39,54)(44,50)(45,52)(46,48)(49,51)(55,56)(2,6)(5,8)(10,16)(14,17)(15,24)(22,23)(25,29,30,31)(26,35,36,44)(27,38,39,45)(28,41,43,42)(32,48,49,55)(33,34,50,40)(37,52,54,53)(46,47,56,51)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.