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