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