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