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