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