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