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