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