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