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