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