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