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