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