One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(11,17)(12,19)(14,21)(16,23)(18,20)(22,24)(25,26,29,32)(27,30,34,39)(28,36,37,31)(33,40,35,38)(2,5)(6,8)(9,10)(11,14)(12,16)(13,15)(17,21)(18,22)(19,23)(20,24)(25,27,29,34)(26,30,32,39)(28,33,37,35)(31,38,36,40)(3,7)(6,8)(9,11,13,18)(10,14,15,22)(12,20,19,17)(16,24,23,21)(27,33)(28,37)(30,38)(31,36)(34,35)(39,40)(1,3,4,7)(2,6,5,8)(10,15)(14,22)(16,23)(21,24)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.