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