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