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