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