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