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