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