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