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