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