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