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