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