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