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