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