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