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