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