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