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