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