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