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