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