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