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