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