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