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)(11,19)(12,16)(13,17)(14,18)(15,21)(20,24)(22,23)(25,26,29,33,30,34,40,46)(27,31,37,43,36,42,49,53)(28,32,39,45,38,44,50,54)(35,41,48,52,47,51,55,56)(3,8)(5,7)(9,11)(10,15)(12,20)(13,22)(14,21)(16,23)(17,24)(18,19)(25,27)(26,31)(28,35)(29,37)(30,36)(32,41)(33,43)(34,42)(38,47)(39,48)(40,49)(44,51)(45,52)(46,53)(50,55)(54,56) involution — undirected(1,3,4,8)(2,5,6,7)(9,12,14,13)(10,16,18,17)(11,20,21,22)(15,23,19,24)(25,28)(26,32)(27,35)(29,39)(30,38)(31,41)(33,45)(34,44)(36,47)(37,48)(40,50)(42,51)(43,52)(46,54)(49,55)(53,56)(2,6)(5,7)(9,13,14,12)(10,17,18,16)(11,20,21,22)(15,23,19,24)(28,38)(32,44)(35,47)(39,50)(41,51)(45,54)(48,55)(52,56)(10,18)(15,19)(16,17)(23,24)(27,36)(31,42)(35,47)(37,49)(41,51)(43,53)(48,55)(52,56) involution — undirectedA 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.