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