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