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