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