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