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