One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,8,12,7,14,6,13)(3,15,18,9,20,33,19,34)(4,21,30,38,25,37,24,10)(5,11,29,40,28,42,27,41)(16,31,22,35,47,53,46,43)(17,48,50,32,52,44,51,62)(23,54,57,36,56,39,26,58)(45,64,49,61,59,60,55,63)(1,3,6,19,7,20,8,18)(2,9,13,15,14,34,12,33)(4,22,24,16,25,46,30,47)(5,17,29,50,28,52,27,51)(10,35,37,31,38,43,21,53)(11,32,40,44,42,62,41,48)(23,55,57,45,56,49,26,59)(36,61,39,60,58,63,54,64)(1,4,6,24,7,25,8,30)(2,10,12,21,14,38,13,37)(3,16,18,22,20,47,19,46)(5,26,27,56,28,57,29,23)(9,31,15,43,34,53,33,35)(11,39,40,58,42,54,41,36)(17,49,50,59,52,55,51,45)(32,61,48,64,62,63,44,60)(1,5,7,28)(2,11)(3,17,20,52)(4,23,25,56)(6,29,8,27)(9,32)(10,36)(12,41)(13,40)(14,42)(15,44)(16,45,47,59)(18,51,19,50)(21,54)(22,55,46,49)(24,57,30,26)(31,60)(33,48)(34,62)(35,61)(37,39)(38,58)(43,63)(53,64)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.