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