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