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