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