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