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