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