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