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