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