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