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