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