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