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