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